help button home button Endocrine Society JCEM
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Submit a related Letter to the Editor
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sloop, K. W.
Right arrow Articles by Rhodes, S. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sloop, K. W.
Right arrow Articles by Rhodes, S. J.
The Journal of Clinical Endocrinology & Metabolism Vol. 85, No. 8 2701-2708
Copyright © 2000 by The Endocrine Society

Original Studies

Molecular Analysis of LHX3 and PROP-1 in Pituitary Hormone Deficiency Patients with Posterior Pituitary Ectopia1

Kyle W. Sloop, Emily C. Walvoord, Aaron D. Showalter2, Ora H. Pescovitz and Simon J. Rhodes

Department of Biology, Indiana University-Purdue University (K.W.S., A.D.S., S.J.R.), and Department of Pediatrics, Section of Endocrinology and Diabetology, Indiana University School of Medicine (E.C.W., O.H.P.), Indianapolis, Indiana 46202

Address all correspondence and requests for reprints to: Simon J. Rhodes, Ph.D., Department of Biology, Indiana University-Purdue University, 723 West Michigan Street, Indianapolis, Indiana 46202-5132. E-mail: srhodes{at}iupui.edu


   Abstract
Top
 Abstract
Introduction
 Experimental Subjects
 Materials and Methods
 Results
 Discussion
 Note Added in Proof
 References
 
The cause of posterior pituitary ectopia associated with anterior pituitary hormone deficiencies is unknown. We describe children with combined pituitary hormone deficiency (CPHD) or isolated GH deficiency. In all cases, magnetic resonance imaging examination revealed abnormal pituitary gland development featuring ectopic posterior lobe location and frequently hypoplastic anterior lobes. Embryonic development of the pituitary requires the coordinated expression of specific transcription factors. Mutations of the PIT-1 and PROP-1 transcription factors are responsible for CPHD in some patients with normally positioned posterior pituitaries. In mice, the Lhx3 LIM homeodomain transcription factor is required for both structural development and cellular differentiation of the pituitary gland. Thus, we hypothesized that mutations in one or both of the two human LHX3 isoforms are responsible for posterior pituitary ectopia associated with anterior pituitary hypopituitarism. Comprehensive molecular analysis of the LHX3 isoforms was performed to test this hypothesis. No loss of function mutations in the LHX3 gene were detected. In addition, analysis of PROP-1 did not reveal mutations that might cause this phenotype. These studies suggest that the abnormal processes leading to the development of CPHD or GH deficiency associated with posterior pituitary ectopia are not a result of aberrant LHX3 or PROP-1 function, but may be caused by defects at other gene loci.


   Introduction
Top
 Abstract
 Introduction
Experimental Subjects
 Materials and Methods
 Results
 Discussion
 Note Added in Proof
 References
 
FORMATION OF the pituitary gland requires the coordination of complex structural and cellular differentiation processes. During embryonic development, neural ectodermal cells from the ventral diencephalon physically associate with ectodermal cells from the oral cavity to form the developing posterior and anterior lobes of the pituitary, respectively. In rodents, the secretion of inductive signaling proteins, such as bone morphogenetic protein-2, bone morphogenetic protein-4, and fibroblast growth factor-8 from these tissues is required for this process (reviewed in Refs. 1, 2). Rathke’s pouch, the primordial anterior lobe structure, originates from cells of the oral ectoderm. The formation and subsequent differentiation of Rathke’s pouch into the mature pituitary gland are regulated by the actions of specific transcription factors in a spatial and temporal fashion. These factors include Rpx/Hesx1, Pitx1, Pitx2, Lhx3/LIM3/P-Lim, Prop-1, and Pit-1/GH factor-1. Gene deletion experiments in mice and the characterization of mutations in animal models and humans have demonstrated that these factors play critical roles in the formation of Rathke’s pouch and the differentiation of the anterior pituitary gland (reviewed in Refs. 3, 4, 5, 6). Mutations in several of these genes have been shown to cause pituitary disease in humans. PIT-1 (POU1F1 gene) mutations lead to combined pituitary hormone deficiency (CPHD) featuring GH, TSH, and PRL deficiencies (7, 8, 9, 10). PROP-1 gene defects lead to CPHD associated with deficiencies in these hormones and often decreased levels of gonadotropins (11, 12, 13, 14, 15, 16). Normal expression of these two factors is restricted to the pituitary, and development of other organ systems is not affected. Interestingly, CPHD patients have been identified who do not have mutations in the coding regions of the PIT-1 or PROP-1 genes (13, 17). These observations suggest that mutations in other pituitary transcription factor genes also may lead to the development of anterior pituitary dysfunction.

CPHD associated with posterior pituitary ectopia is a form of pituitary dysfunction of unknown etiological origin. Aberrant pituitary development featuring ectopically located posterior pituitary glands has been described since the introduction of magnetic resonance imaging (MRI) and is visualized as a high intensity signal, or bright spot, on T1 weighted, noncontrast images. The posterior pituitary bright spot can be found at the median eminence of the hypothalamus or anywhere along the normal path of the infundibulum. This condition is usually found in association with hypoplastic anterior pituitary glands in patients with either CPHD or isolated GH deficiency (GHD) (18, 19, 20, 21, 22, 23). Posterior pituitary function is almost always normal in these patients, as diabetes insipidus is extremely uncommon (19, 20, 21, 23).

Previous reports describing this form of pituitary dysgenesis have suggested the condition to be the result of injury to the pituitary stalk during childbirth (18, 23). Other studies, however, propose a congenital cause for this form of pituitary disease (19, 22, 24, 25, 26). A defect in an anterior pituitary gland expressed gene may be responsible for this disease because patients with posterior pituitary ectopia typically have small or absent anterior lobes (19, 21, 24, 27). The presence of the anterior pituitary gland in anencephalic fetuses that are without a hypothalamus or posterior lobe also indicates that differentiation of the hormone-secreting cell types of the human anterior lobe may not require the presence of these structures (28). These observations support the suggestion that the mutation responsible for the ectopic posterior pituitary CPHD phenotype resides in a gene critical to anterior gland development because these patients usually have underdeveloped, hypoplastic anterior lobes. Two groups recently examined whether PIT-1 might be a candidate gene in the etiology of CPHD associated with posterior pituitary ectopia (19, 25). However, PIT-1 gene mutations were not found in the patients examined. These patients also had no identifiable mutations of the GH (19, 25) or GHRH receptor genes (19).

Lhx3 is a LIM homeodomain transcription factor that is transiently expressed in the developing neural cord and brainstem and then is restricted to the developing and adult pituitary gland (29, 30, 31, 32, 33). The presence of Lhx3 expression when the oral ectodermal cells of Rathke’s pouch contact the neural ectoderm cells that become the posterior lobe suggested that Lhx3 is necessary for pituitary gland formation (29, 30, 31). Consistent with this hypothesis, the development of Rathke’s pouch is arrested in mice with deleted Lhx3 genes, and hormone-secreting cell types are not produced (34). These studies demonstrate that Lhx3 is required for both early structural development and late cellular differentiation of the pituitary gland. Two LHX3 isoforms (LHX3a and LHX3b) exist in humans that share common LIM and DNA-binding domains, but possess distinct amino terminal sequences (33). We recently demonstrated that these factors differ in their abilities to activate pituitary hormone gene targets, suggesting distinct functions of these isoforms during human development (33).

Because the LHX3 factors appear to be important for early formative processes and later cellular specification events of the developing pituitary gland, we hypothesized that LHX3 is a candidate gene that when mutated would cause ectopic posterior pituitary disease associated with anterior pituitary hypopituitarism. Molecular analysis of the LHX3 gene in patients with posterior pituitary ectopia was performed to test this hypothesis. In addition, because hormone deficiencies vary among CPHD patients with PROP-1 mutations, the patients in this study were screened for the recently described PROP-1 gene hot spot deletion mutation (12, 15).


   Experimental Subjects
Top
 Abstract
 Introduction
 Experimental Subjects
Materials and Methods
 Results
 Discussion
 Note Added in Proof
 References
 
Subjects were selected based on the finding of an ectopic posterior pituitary gland on MRI from a group of 290 patients with either CPHD or GHD who presented with short stature or varying symptoms of hypopituitarism. CPHD was defined as GHD in combination with at least 1 other deficiency of an anterior pituitary hormone. All 9 patients had an ectopic hyperintense signal of the neurohypophysis visualized on MRI scanning. Perinatal data, such as gestational age, birth weight, method of delivery, breech or vertex presentation, complications at delivery, as well as prenatal history, were recorded. The study protocol was approved by the institutional review board of Indiana University. Informed consent was obtained from the parents of all of the subjects and from the subjects themselves if they were 8 yr of age or older.


   Materials and Methods
Top
 Abstract
 Introduction
 Experimental Subjects
 Materials and Methods
Results
 Discussion
 Note Added in Proof
 References
 
Hormone evaluation and stimulation tests

GHD was diagnosed as a peak GH response of less than 10 ng/mL after two of the following pharmacological stimulation tests: arginine HCl (0.5 g/kg, iv), clonidine (50 µg, orally), or levodopa (125–500 mg, orally; dose determined by the patient’s weight). TSH insufficiency was diagnosed by either a free T4 less than 0.8 ng/dL or, in two patients, a low T4 level in combination with a normal TSH level. This presentation is typical of patients with hypothalamic-pituitary hypothyroidism. ACTH insufficiency was diagnosed by either a single dose metyrapone test resulting in a Compound S (11-deoxycortisol) level of less than 7 µg/dL or by high dose ACTH stimulation test resulting in a plasma cortisol response of less than 25 µg/dL. Routine evaluations of the pituitary-gonadal axis were not performed. Patients were considered gonadotropin sufficient if they spontaneously entered puberty. Patients were considered gonadotropin insufficient if they required sex steroid replacement to induce puberty.

Pituitary magnetic imaging

MRI scanning obtained specific pituitary cuts of 3-mm-thick slices on sagittal and coronal views of the pituitary. All MRIs were reviewed by one of two pediatric neuroradiologists who were aware only that the subjects had growth failure. Associated brain abnormalities seen on MRI also were noted.

Diagnostic procedures to detect mutations in LHX3

Genomic DNA was extracted from peripheral blood using a QIAamp Blood Maxi Kit (QIAGEN, Valencia, CA). LHX3 exons were amplified by the PCR using primers specific to LHX3 intronic DNA sequences (35). Each PCR reaction contained 2.5 U Expand High Fidelity DNA polymerase mixture (Roche, Indianapolis, IN); 10 mmol/L deoxy (d)-ATP, dCTP, dGTP, and dTTP; 200 ng human genomic DNA; and 10 pmol of each forward and reverse primer. Primers to amplify each exon were as follows: exon Ia, 5'-tgacctcggaggagcgcgtct-3' and 5'-caaccgctgtcccgcactctt-3'; exon Ib, 5'-gaaagttcgggactggagagt-3' and 5'-cagtgccacaacctcactca-3'; exon II, 5'-tacgaggtgacccagaactt-3' and 5'-cctggccttggtgattgtga-3'; exon III, 5'-tttcagaccaggaaaggtgg-3' and 5'-cgaaatgagcctcgcgcttc-3'; exons IV and V, 5'-gctgccgcgcctcaccgct-3' and 5'-aggagtccactaactccatg-3'; and exon VI, 5'-cgctgactgagcctctgctt-3' and 5'-cctcgtgtgaggtgcagggt-3'. PCR cycling parameters were as follows: 94 C for 2 min, 94 C for 10 s, 60 C for 10 s, and 72 C for 1 min for 25 cycles. Reaction products were analyzed for gross abnormalities on 1% agarose/Tris-borate gels and subsequently ligated into pCRII-TOPO (Invitrogen, Carlsbad, CA). DNA sequencing was performed on both strands by automated DNA sequencing using a Perkin-Elmer Corp. DNA Sequencer (Biochemistry Biotechnology Facility, Indiana University School of Medicine). Six PCR products of each amplified exon were sequenced from each individual patient to ensure more than 98% confidence of characterization of both alleles.

Diagnostic procedures for PROP-1 analysis

PCR was used to amplify exon 2 of PROP-1 from the genomic DNA of each patient for restriction endonuclease digestion analysis for the {Delta}A301{Delta}G302 deletion mutation. The primers used were 5'-acaggcacatgtggtccagca-3' and 5'-ccaacattctatgatagcacca-3'. PCR conditions were the same as those for LHX3. PCR products were analyzed for gross abnormalities by gel electrophoresis and then ethanol precipitated. BcgI restriction endonuclease digestion reactions of exon 2 from each patient included 6 U BcgI and S-adenosylmethionine (New England Biolabs, Inc., Beverly, MA). PvuII (New England Biolabs, Inc.) restriction endonuclease digestion was performed on each sample as a positive control. In addition, exon 2 of PROP-1 from two patients was ligated into pCRII-TOPO and sequenced.


   Results
Top
 Abstract
 Introduction
 Experimental Subjects
 Materials and Methods
 Results
Discussion
 Note Added in Proof
 References
 
Phenotypic features of patients

Five subjects were male, and four were female. The mean age at diagnosis was 5.5 yr, with a range of 5 weeks to 10 yr. The presenting complaint in all subjects was short stature, except for the 5-week-old who presented with hypoglycemic seizures. All subjects had complete GHD, with all peak GH responses being 5 ng/dL or less (Table 1Go). Two subjects had isolated GHD, one subject had only GHD and TSH deficiency, and the remaining six had GHD, TSH, and ACTH deficiencies. Two subjects had spontaneously entered puberty at the time of the analysis. Two subjects were considered to have presumptive gonadotropin deficiency: one girl had not developed any secondary sexual characteristics by age 14 yr and was thus started on estrogen therapy, and one boy had a congenital micropenis.


View this table:
[in this window]
[in a new window]
  		Table 1. Clinical and laboratory evaluation of patients

 
Six subjects were born at full term with vertex presentations and normal birth weights. Five of the six were vaginal deliveries, and the sixth was delivered by elective, repeat cesarean section (C/S). One subject was born prematurely at 32 weeks gestation via C/S due to concerns of oligohydramnios and placenta previa. Another subject was delivered via emergency C/S at 34 weeks gestation because of uterine rupture that occurred after a motor vehicle accident. This child also suffered a depressed skull fracture and an underlying left internal capsular stroke that resulted in right-sided hemiparesis. A third subject was born at 30 weeks gestation after failed tocolytic therapy for preterm labor of unknown etiology. This child was delivered by C/S for breech presentation.

MRI scanning revealed ectopic posterior pituitary glands in all nine subjects (Fig. 1Go). One subject had no visible anterior pituitary tissue, seven had hypoplastic anterior pituitary glands, and one had a normal appearing anterior pituitary gland. Two subjects had Chiari I malformations, and another had mildly enlarged posterior horns of the lateral ventricles that were believed to be of no clinical significance.



View larger version (84K):
[in this window]
[in a new window]
  		Figure 1. A, Sagittal MRI section of the pituitary region of patient F revealing a small anterior pituitary (small arrow) and an ectopically located posterior pituitary (large arrow) near the base of the hypothalamus. B, Coronal view of the same subject demonstrating a hypoplastic anterior pituitary (small arrow) and an ectopic posterior pituitary (large arrow) visualized as a bright spot at the level of the optic chiasm.

 
Molecular analysis of LHX3

Analysis of the LHX3 isoforms was performed using genomic DNA from each subject in this study. The LHX3 gene contains seven exons that code for the functional domains of the two factors (35). No previous reports have examined whether mutations in this gene lead to a disease phenotype. Thus, a comprehensive screening strategy was designed to amplify exons encoding the alternate amino-termini (exons Ia and Ib), LIM1 (exon II) and LIM2 (exon III), the homeodomain (exons IV and V), and the Lhx3/LIM3-specific domain (exon VI; Fig. 2AGo). Because the LHX3 gene is highly GC rich, primer optimization was performed to enable PCR amplifications yielding specific products that allowed efficient subcloning and DNA sequencing analyses: exon Ib, 335 bp; exon Ib, 346 bp; exon II, 291 bp; exon III, 296 bp; exons IV and V, 553 bp; and exon VI, 483 bp (Fig. 2BGo). Six independent PCR products were sequenced on both strands for each exon of all patients examined. This strategy assured with more than 98% confidence that both LHX3 alleles were assessed. An A->G substitution at nucleotide 81 of exon Ib was identified in patients C (heterozygous), D (homozygous), E (homozygous), H (heterozygous), I (heterozygous), J (heterozygous), and K (homozygous; Fig. 2CGo). The A->G substitution occurs in the wobble position of an alanine codon (A27) of LHX3b and does not change the protein sequence. In addition, a C->T substitution at nucleotide 19 of intron 1b was identified in patients I (heterozygous) and K (heterozygous). These positions are therefore polymorphic. No other nucleotide changes were found in the LHX3 genes of these patients.



View larger version (24K):
[in this window]
[in a new window]
  		Figure 2. Molecular analysis of the LHX3 gene. A, Strategy for amplification of LHX3 exons. Boxes represent exons, which are labeled in Roman numerals. Introns are labeled in Arabic numerals. Arrows indicate the positions of PCR primers used to amplify LHX3 exons for DNA sequencing analyses. B, PCR-amplified products representing each LHX3 exon of patient C. C, Schematic depiction of the LHX3 gene indicating the positions of the identified polymorphisms and frequencies in the analyzed population.

 
Molecular analysis of PROP-1

The previously described PROP-1 {Delta}A301{Delta}G302 deletion mutation creates a BcgI restriction endonuclease site in exon 2 of the PROP-1 gene (12, 15). PCR was used to amplify exon 2 of PROP-1 (373 bp) from genomic DNA of each patient (Fig. 3AGo). BcgI restriction endonuclease digestion of exon 2 did not identify the {Delta}A301{Delta}G302 deletion mutation in any of these patients (Fig. 3BGo and data not shown; resulting fragments would be 246, 91, and 34 bp if the mutation was present). As a positive control for BcgI endonuclease activity, LHX3 exon Ib (346 bp), which contains a BcgI site, was digested into three fragments. In addition, as a positive control to ensure the PROP-1 PCR products could be cut by a restriction endonuclease, each amplified exon 2 was digested with PvuII to generate two fragments (211 and 162 bp; Fig. 3CGo and data not shown). Also, the amplified PROP-1 exon 2 fragments of patients D and H were subcloned and completely sequenced. No mutations in PROP-1 were identified in these patients.



View larger version (86K):
[in this window]
[in a new window]
  		Figure 3. Molecular analysis of the PROP-1 gene deletion mutation. A, PCR amplification of PROP-1 exon 2 from the indicated patients. B, BcgI restriction endonuclease digestion of PROP-1 exon 2. +, Positive control for BcgI activity (cut and uncut). C, Control PvuII restriction endonuclease digestion of PROP-1 exon 2.

 

   Discussion
Top
 Abstract
 Introduction
 Experimental Subjects
 Materials and Methods
 Results
 Discussion
Note Added in Proof
 References
 
The cause of the ectopic location of the posterior pituitary gland in some subjects with hypopituitarism is currently unknown. Early reports found a high incidence of breech delivery in patients with ectopic posterior pituitaries, and it was postulated that anoxic or shearing force injury was the cause of the ectopically located gland (18, 27). However, more recent studies have not found the same association, and it is now believed that the high incidence of breech presentations in these patients is secondary to abnormalities of the neuroendocrine system (26). Currently, it is hypothesized that the posterior lobe fails to descend normally due to a vascular disruption (21) or a genetic mutation affecting migration (22, 24). For example, a familial form of ectopic posterior pituitarism in twin boys with other associated midline defects has been described (36).

We characterized the clinical phenotype of nine patients with ectopic posterior pituitary glands. MRI analysis revealed that the majority of these patients have a small or absent anterior pituitary gland, a truncated infundibulum, and an ectopic posterior pituitary hyperintensity signal located at the base of the hypothalamus. All patients had isolated GHD or GHD in combination with other anterior pituitary hormone deficiencies. We analyzed the perinatal periods of the children, and a causal relationship between perinatal injuries and the pituitary developmental abnormalities could not be established. Because birth injury does not appear to contribute to abnormal pituitary development in our patients, we hypothesized that a defect in a gene critical to pituitary embryogenesis may be responsible for this disease condition.

The Lhx3 LIM homeodomain transcription factor is required for pituitary development in rodents. Lhx3 null mutant mice fail to develop a mature pituitary gland structure and anterior pituitary hormone-secreting cell types (34). Although Rathke’s pouch fails to differentiate into the mature pituitary in these animals, more subtle gene defects may result in a less severe phenotype, such as a structurally compromised, but partially functional, pituitary. The phenotype of Pit-1 mutant Snell and Jackson dwarf mice is mimicked in humans with PIT-1 gene mutations; however, hormone deficiencies in humans with PROP-1 mutations are varied among affected individuals and do not completely match those of Prop-1 mutant Ames dwarf mice (reviewed in Refs. 3, 4). Because Lhx3 is necessary for both the initial structural formation of Rathke’s pouch and the subsequent cellular differentiation required for development of the mature pituitary, we considered it a candidate to cause the abnormal pituitary development and maturation in patients with posterior pituitary ectopia.

A comprehensive approach was used to test for mutations in LHX3. Mutations in functional domains of several transcription factors are known to compromise their activity and cause disease (7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 37, 38). These defects often reside in the DNA-binding homeodomain. Our laboratory and others have demonstrated that the LHX3 isoforms contain multiple domains that are required for proper protein function (29, 30, 31, 32, 33). Two functionally distinct LHX3 isoforms exist that differ in their amino-termini, but share two common LIM domains, a homeodomain, and an Lhx3/LIM3-specific domain (31, 33). We recently demonstrated that these functional domains are encoded by distinct exons (35). Because multiple regions of the LHX3 isoforms play critical functional roles, we analyzed each region for mutations that might compromise the activity of the encoded proteins. Only an A->G substitution in exon Ib and a C->T substitution in intron 1b were identified. These are the first polymorphisms to be identified in LHX3; however, the exon Ib substitution does not change the amino acid coding sequence as it is found in the wobble position of an alanine codon. This polymorphism was found in both alleles of three patients and in one allele of four others. No other nucleotide changes were identified in the LHX3-coding regions of these patients. The intron 1b substitution was identified in one allele of two patients. Although single nucleotide polymorphisms have been demonstrated to affect translation efficiencies of messenger ribonucleic acids and have been hypothesized as potential causes of disease (39), this does not appear to be the cause of posterior pituitary ectopia because affected patients were identified without the substitutions. We conclude that the described posterior pituitary condition is not a result of mutations in the LHX3 gene, although promoter/gene regulatory elements were not examined.

Many reports have demonstrated that PIT-1 and PROP-1 mutations result in CPHD, but none has described mutations in these genes associated with an ectopic posterior pituitary. Two groups recently tested ectopic posterior pituitary patients for PIT-1 mutations but failed to identify defects in this gene (19, 25). It appears that PIT-1 gene mutations result in CPHD without abnormal positioning of the posterior pituitary. We considered PROP-1 a candidate gene and screened the patients in this study for the recently described PROP-1 gene hot spot deletion mutation (12, 15). Genomic analysis did not identify this mutation in any of our patients.

Unfortunately, a mouse model representing the ectopic posterior and hypoplastic anterior pituitary gland phenotype does not exist. Gene deletion experiments in mice and mutations in humans have demonstrated that defects in pituitary transcription factors cause abnormal pituitary development and disease. However, current data suggest that mutations in several of these candidate genes may lead to broader developmental disorders affecting other systems in addition to the pituitary. For example, PITX2 mutations identified in humans cause Reiger syndrome (40, 41). Humans and mice with mutations in HESX1 have CPHD but also display septo-optic dysplasia (42). Similarly, Pitx1 knockout mice develop abnormal jaw and hindlimb structures (43, 44). Because the ectopic posterior pituitary gland phenotype has yet to be recapitulated in a mouse knockout model, the gene responsible for this condition may not yet be identified at this time.

This study is one of the first to test whether mutations in the LHX3 gene cause human pituitary disease and is the first analysis of PROP1 in CPHD patients that have ectopically positioned posterior pituitary glands. Molecular analysis of these factors failed to identify genetic lesions responsible for this condition. The molecular basis for dysgenesis leading to the ectopic posterior and hypoplastic anterior pituitary gland phenotype of these patients remains unclear. Future analyses will examine the promoter regions of these genes and the genomic loci of other transcription factors and signaling molecules important during pituitary embryogenesis. Mutations in LHX3 may cause other pituitary or central nervous system disorders.


   Note Added in Proof
Top
 Abstract
 Introduction
 Experimental Subjects
 Materials and Methods
 Results
 Discussion
 Note Added in Proof
References
 
After the acceptance of this manuscript, Netchine et al. (Nat Genet. 25:182, 2000) described CPHD patients with mutations in the LHX3 gene.


   Acknowledgments
 
We thank M. Kennedy for technical advice and Dr. Mary Edwards-Brown for retrospective review of MRI images.


   Footnotes
 
1 This work was supported by grants from the NSF and the National Research Initiative Competitive Grants Program/USDA (to S.J.R.), the Genentech Center for Clinical Research and Education (fellowship award to E.C.W.), and the NIH (Grant R01-HD-34789; to O.H.P.). Back

2 Recipient of an Endocrine Society Summer Fellowship. Back

Received January 11, 2000.

Revised March 30, 2000.

Accepted April 17, 2000.


   References
Top
 Abstract
 Introduction
 Experimental Subjects
 Materials and Methods
 Results
 Discussion
 Note Added in Proof
 References
 

  1. Dasen JS, Rosenfeld MG. 1999 Combinatorial codes in signaling and synergy: lessons from pituitary development. Curr Opin Genet Dev. 9:566–574.[CrossRef][Medline]
  2. Sheng HZ, Westphal H. 1999 Early steps in pituitary organogenesis. Trends Genet. 15:236–240.[CrossRef][Medline]
  3. Parks JS, Brown MR, Hurley DL, Phelps CJ, Wajnrajch MP. 1999 Heritable disorders of pituitary development. J Clin Endocrinol Metab. 84:4362–4370.[Abstract/Free Full Text]
  4. Parks JS, Brown MR. 1999 Transcription factors regulating pituitary development. Growth Horm IGF Res. 9(Suppl B):2–8.
  5. Burrows HL, Douglas KR, Seasholtz AF, Camper SA. 1999 Genealogy of the anterior pituitary gland: tracing a family tree. Trends Endocrinol Metab. 10:343–352.[CrossRef][Medline]
  6. Cohen LE, Radovick S, Wondisford FE. Transcription factors and hypopituitarism. Trends Endocrinol Metab. 10:326–332.
  7. Tatsumi K, Miyai K, Notomi T, et al. 1992 Cretinism with combined hormone deficiency caused by a mutation in the PIT1 gene. Nat Genet. 1:56–58.[CrossRef][Medline]
  8. Radovick S, Nations M, Du Y, Berg LA, Weintraub BD, Wondisford FE. 1992 A mutation in the POU-homeodomain of Pit-1 responsible for combined pituitary hormone deficiency. Science. 257:1115–1118.[Abstract/Free Full Text]
  9. Pfäffle RW, DiMattia GE, Parks JS, et al. 1992 Mutation of the POU-specific domain of Pit-1 and hypopituitarism without pituitary hypoplasia. Science. 257:1118–1121.[Abstract/Free Full Text]
  10. Ohta K, Nobukuni Y, Mitsubuchi H, et al. 1992 Mutations in the Pit-1 gene in children with combined pituitary hormone deficiency. Biochem Biophys Res Commun. 189:851–855.[CrossRef][Medline]
  11. Wu W, Cogan JD, Pfäffle RW, et al. 1998 Mutations in PROP1 cause familial combined pituitary hormone deficiency. Nat Genet. 18:147–149.[CrossRef][Medline]
  12. Cogan JD, Wu W, Phillips JA. 3rd, et al. The PROP1 2-base pair deletion is a common cause of combined pituitary hormone deficiency. J Clin Endocrinol Metab. 83:3346–3349.
  13. Fofanova O, Takamura N, Kinoshita E, et al. 1998 Compound heterozygous deletion of the PROP-1 gene in children with combined pituitary hormone deficiency. J Clin Endocrinol Metab. 83:2601–2604.[Abstract/Free Full Text]
  14. Duquesnoy P, Roy A, Dastot F, et al. 1998 Human Prop-1: cloning, mapping, genomic structure. Mutations in familial combined pituitary hormone deficiency. FEBS Lett. 437:216–220.[CrossRef][Medline]
  15. Deladoey J, Fluck C, Buyukgebiz A, et al. 1999 "Hot spot" in the PROP1 gene responsible for combined pituitary hormone deficiency. J Clin Endocrinol Metab. 84:1645–1650.[Abstract/Free Full Text]
  16. Nogueira CR, Sabacan L, Jameson JL, Medeiros-Neto G, Kopp P. 1999 Combined pituitary hormone deficiency in an inbred Brazilian kindred associated with a mutation in the PROP-1 gene. Mol Genet Metab. 67:58–61.[CrossRef][Medline]
  17. Pfäffle RW, Kim C, Blankenstein O, Kentrup H. 1999 GH transcription factors. J Pediatr Endocrinol Metab. 12:311–317.
  18. Fujisawa I, Kikuchi K, Nishimura K, et al. 1987 Transection of the pituitary stalk: development of an ectopic posterior lobe assessed with MR imaging. Radiology. 165:487–489.[Abstract/Free Full Text]
  19. Pinto G, Netchine I, Sobrier ML, Brunelle F, Souberbielle JC, Brauner RJ. 1999 Pituitary stalk interruption syndrome: a clinical-biological-genetic assessment of its pathogenesis. J Clin Endocrinol Metab. 82:3450–3454.[Abstract/Free Full Text]
  20. Abrahams JJ, Trefelner E, Boulware SD. 1991 Idiopathic growth hormone deficiency: MR findings in 35 patients. Am J Neuroradiol. 12:155–160.[Abstract]
  21. Kelly WM, Kucharczyk W, Kucharczyk J, et al. 1988 Posterior pituitary ectopia: an MR feature of pituitary dwarfism. Am J Neuroradiol. 9:453–460.[Abstract]
  22. Nagel BH, Palmbach M, Petersen D, Ranke MB. 1997 Magnetic resonance images of 91 children with different causes of short stature: pituitary size reflects growth hormone secretion. Eur J Pediatr. 156:758–763.[CrossRef][Medline]
  23. Kikuchi K, Fujisawa I, Momoi T, et al. 1988 Hypothalamic-pituitary function in growth hormone-deficient patients with pituitary stalk transection. J Clin Endocrinol Metab. 67:817–823.[Abstract/Free Full Text]
  24. Chen S, Leger J, Garel C, Hassan M, Czernichow PJ. 1999 Growth hormone deficiency with ectopic neurohypophysis: anatomical variations and relationship between the visibility of the pituitary stalk asserted by magnetic resonance imaging and anterior pituitary function. J Clin Endocrinol Metab. 84:2408–2413.[Abstract/Free Full Text]
  25. Hamilton J, Chitayat D, Blaser S, Cohen LE, Phillips III JA, Daneman D. 1998 Familial growth hormone deficiency associated with MRI abnormalities. Am J Med Genet. 80:128–132.[CrossRef][Medline]
  26. Maghnie M, Larizza D, Triulzi F, Sampaolo P, Scotti G, Severi, F. 1991 Hypopituitarism and stalk agenesis: a congenital syndrome worsened by breech delivery? Horm Res. 35:104–108.[Medline]
  27. Kuroiwa T, Okabe Y, Hasuo K, Yasumori K, Mizushima A, Masuda, K. 1991 MR imaging of pituitary dwarfism. Am J Neuroradiol. 12:161–164.[Abstract]
  28. Pilavdzic D, Kovacs K, Asa SL. 1997 Pituitary morphology in anencephalic human fetuses. Neuroendocrinology. 65:164–172.[Medline]
  29. Seidah NG, Barale JC, Marcinkiewicz M, Mattei MG, Day R, Chretien M. 1994 The mouse homeoprotein mLIM-3 is expressed early in cells derived from the neuroepithelium and persists in adult pituitary. DNA Cell Biol. 13:1163–1180.[Medline]
  30. Bach I, Rhodes SJ, Pearse Jr RV, et al. 1995 P-Lim, a LIM homeodomain factor, is expressed during pituitary organ and cell commitment and synergizes with Pit-1. Proc Natl Acad Sci USA. 92:2720–2724.[Abstract/Free Full Text]
  31. Zhadanov AB, Bertuzzi S, Taira M, Dawid IB, Westphal H. 1995 Expression pattern of the murine LIM class homeobox gene Lhx3 in subsets of neural and neuroendocrine tissues. Dev Dyn. 202:354–364.[Medline]
  32. Meier BC, Price JR, Parker GE, Bridwell JL, Rhodes SJ. 1999 Characterization of the porcine Lhx3/LIM-3/P-Lim LIM homeodomain transcription factor. Mol Cell Endocrinol. 147:65–74.[CrossRef][Medline]
  33. Sloop KW, Meier BC, Bridwell JL, Parker GE, McCutchan Schiller A, Rhodes SJ. 1999 Differential activation of pituitary hormone genes by human Lhx3 isoforms with distinct DNA binding properties. Mol Endocrinol. 13:2212–2225.[Abstract/Free Full Text]
  34. Sheng HZ, Zhadanov AB, Mosinger Jr B, et al. 1996 Specification of pituitary cell lineages by the LIM homeobox gene Lhx3. Science. 272:1004–1007.[Abstract]
  35. Sloop KW, Showalter AD, Von Kap-Herr C, Pettenati MJ, Rhodes SJ. 2000 Analysis of the human LHX3 neuroendocrine transcription factor gene and mapping to the subtelomeric region of chromosome 9. Gene. 245:237–243.[CrossRef][Medline]
  36. Siegel SF, Ahdab-Barmada M, Arslanian S, Foley TP Jr. 1995 Ectopic posterior pituitary tissue, and paracentric inversion of the short arm of chromosome 1 in twins. Eur J Endocrinol. 133:87–92.[Abstract/Free Full Text]
  37. Clifton-Bligh RJ, Wentworth JM, Heinz P, et al. 1998 Mutation of the gene encoding human TTF-2 associated with thyroid agenesis, cleft palate and choanal atresia. Nat Genet. 19:399–401.[CrossRef][Medline]
  38. Dreyer SD, Zhou G, Baldini A, et al. 1998 Mutations in LMX1B cause abnormal skeletal patterning and renal dysplasia in nail patella syndrome. Nat Genet. 19:47–50.[CrossRef][Medline]
  39. Shen LX, Basilion JP, Stanton Jr VP. 1999 Single-nucleotide polymorphisms can cause different structural folds of mRNA. Proc Natl Acad Sci USA. 96:7871–7876.[Abstract/Free Full Text]
  40. Semina EV, Reiter R, Leysens NJ, et al. 1996 Cloning and characterization of a novel bicoid-related homeobox transcription factor gene, RIEG, involved in Rieger syndrome. Nat Genet. 14:392–399.[CrossRef][Medline]
  41. Amendt BA, Sutherland LB, Semina EV, Russo AF. 1998 The molecular basis of Rieger syndrome. Analysis of Pitx2 homeodomain protein activities. J Biol Chem. 273:20066–20072.[Abstract/Free Full Text]
  42. Dattani MT, Martinez-Barbera JP, Thomas PQ, et al. 1998 Mutations in the homeobox gene HESX1/Hesx1 associated with septo-optic dysplasia in human and mouse. Nat Genet. 19:125–133.[CrossRef][Medline]
  43. Lanctot C, Moreau A, Chamberland M, Tremblay ML, Drouin J. 1999 Hindlimb patterning and mandible development require the Ptx1 gene. Development. 126:1805–1810.[Abstract]
  44. Szeto DP, Rodriguez-Esteban C, Ryan AK, et al. 1999 Role of the bicoid-related homeodomain factor Pitx1 in specifying hindlimb morphogenesis and pituitary development. Genes Dev. 13:484–494.[Abstract/Free Full Text]



This article has been cited by other articles:


Home page
 J. Clin. Endocrinol. Metab.Home page
R. W. Pfaeffle, J. J. Savage, C. S. Hunter, C. Palme, M. Ahlmann, P. Kumar, J. Bellone, E. Schoenau, E. Korsch, J. H. Bramswig, et al.
Four Novel Mutations of the LHX3 Gene Cause Combined Pituitary Hormone Deficiencies with or without Limited Neck Rotation
J. Clin. Endocrinol. Metab., May 1, 2007; 92(5): 1909 - 1919.
[Abstract] [Full Text] [PDF]

Home page
 J. Clin. Endocrinol. Metab.Home page
R. Reynaud, M. Gueydan, A. Saveanu, S. Vallette-Kasic, A. Enjalbert, T. Brue, and A. Barlier
Genetic Screening of Combined Pituitary Hormone Deficiency: Experience in 195 Patients
J. Clin. Endocrinol. Metab., September 1, 2006; 91(9): 3329 - 3336.
[Abstract] [Full Text] [PDF]

Home page
 J. Clin. Endocrinol. Metab.Home page
A. P. S. Bhangoo, C. S. Hunter, J. J. Savage, H. Anhalt, S. Pavlakis, E. C. Walvoord, S. Ten, and S. J. Rhodes
A Novel LHX3 Mutation Presenting as Combined Pituitary Hormonal Deficiency
J. Clin. Endocrinol. Metab., March 1, 2006; 91(3): 747 - 753.
[Abstract] [Full Text] [PDF]

Home page
 EndocrinologyHome page
B. E. West, G. E. Parker, J. J. Savage, P. Kiratipranon, K. S. Toomey, L. R. Beach, S. C. Colvin, K. W. Sloop, and S. J. Rhodes
Regulation of the Follicle-Stimulating Hormone {beta} Gene by the LHX3 LIM-Homeodomain Transcription Factor
Endocrinology, November 1, 2004; 145(11): 4866 - 4879.
[Abstract] [Full Text] [PDF]

This Article
Right arrow Abstract Freely available
Right arrow Full Text (PDF)
Right arrow Submit a related Letter to the Editor
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Sloop, K. W.
Right arrow Articles by Rhodes, S. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Sloop, K. W.
Right arrow Articles by Rhodes, S. J.

HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals