Three Novel Missense Mutations within the LHX4 Gene Are Associated with Variable Pituitary Hormone Deficiencies

Abstract Context: The LHX4 LIM-homeodomain transcription factor has essential roles in pituitary gland and nervous system development. Heterozygous mutations in LHX4 are associated with combined pituitary hormone deficiency. Objectives: Our objectives were to determine the nature and frequency of LHX4 mutations in patients with pituitary hormone deficiency and to examine the functional outcomes of observed mutations. Design: The LHX4 gene sequence was determined from patient DNA. The biochemical and gene regulatory properties of aberrant LHX4 proteins were characterized using structural predictions, pituitary gene transcription assays, and DNA binding experiments. Patients: A total of 253 patients from 245 pedigrees with GH deficiency and deficiency of at least one additional pituitary hormone was included in the study. Results: In five patients, three types of heterozygous missense mutations in LHX4 that result in substitution of conserved amino acids were identified. One substitution is between the LIM domains (R84C); the others are in the homeodomain (L190R; A210P). The patients have GH deficiency; some also display reductions in TSH, LH, FSH, or ACTH, and aberrant pituitary morphology. Structural models predict that the aberrant L190R and A210P LHX4 proteins would have impaired DNA binding and gene activation properties. Consistent with these models, EMSAs and transfection experiments using pituitary gene promoters demonstrate that whereas the R84C form has reduced activity, the L190R and A210P proteins are inactive. Conclusions: LHX4 mutations are a relatively rare cause of combined pituitary hormone deficiency. This report extends the range of phenotypes associated with LHX4 gene mutations and describes three novel exonic mutations in the gene.

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Novel Mutations within the POU1F1 Gene Associated with Variable Combined Pituitary Hormone Deficiency

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2005-0570 ◽

2005 ◽

Vol 90 (8) ◽

pp. 4762-4770 ◽

Cited By ~ 72

Author(s):

James P. G. Turton ◽

Rachel Reynaud ◽

Ameeta Mehta ◽

John Torpiano ◽

Alexandru Saveanu ◽

...

Keyword(s):

Dna Binding ◽

Mutational Analysis ◽

Hot Spot ◽

Dominant Negative ◽

Hormone Deficiency ◽

Pituitary Hormone ◽

Novel Mutations ◽

Pituitary Hormone Deficiency ◽

Combined Pituitary Hormone Deficiency ◽

Functional Studies

Context: Mutations within the gene encoding the pituitary-specific transcription factor POU1F1 are associated with combined pituitary hormone deficiency (CPHD). Most of the affected individuals manifest GH, prolactin, and TSH deficiency. Objective: We have now screened 129 individuals with CPHD and isolated GH deficiency for mutations within POU1F1. Results: Causative mutations were identified in 10 of 129 individuals (7.8%). Of these, five patients harbored the dominant negative R271W mutation, which is a well-recognized mutational hot spot. We have also identified a second frequently occurring mutation, E230K, which appears to be common in Maltese patients. Additionally, we describe two novel mutations within POU1F1, an insertion of a single base pair (ins778A) and a missense mutation (R172Q). Functional studies have revealed that POU1F1 (E230K) is associated with a reduction in transactivation, although DNA-binding affinity is similar to the wild-type protein. On the other hand, POU1F1 (R172Q) is associated with a reduction in DNA binding and transactivation, whereas POU1F1 (ins778A) is associated with loss of DNA binding and a reduction in transactivation. Conclusions: Our data suggest that the phenotype associated with POU1F1 mutations may be more variable, with the occasional preservation of TSH secretion. Additionally, our data revealed POU1F1 mutations in three patients who were diagnosed as having ACTH deficiency but who, on further evaluation, were found to have normal cortisol secretion. Hence, elucidation of the genotype led to further evaluation of the phenotype, with the cessation of cortisol replacement that had been commenced unnecessarily. These data reflect the importance of mutational analysis in patients with CPHD.

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Four Novel Mutations of the LHX3 Gene Cause Combined Pituitary Hormone Deficiencies with or without Limited Neck Rotation

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2006-2177 ◽

2007 ◽

Vol 92 (5) ◽

pp. 1909-1919 ◽

Cited By ~ 80

Author(s):

Roland W. Pfaeffle ◽

Jesse J. Savage ◽

Chad S. Hunter ◽

Christina Palme ◽

Martina Ahlmann ◽

...

Keyword(s):

Dna Binding ◽

Gh Deficiency ◽

Gene Activation ◽

Gene Mutations ◽

Biochemical Properties ◽

Hormone Deficiency ◽

Pituitary Hormone ◽

Molecular Defects ◽

Recessive Mutations ◽

Neck Rotation

Abstract Context: The Lhx3 LIM-homeodomain transcription factor gene is required for development of the pituitary and motoneurons in mice. Human LHX3 gene mutations have been reported in five subjects with a phenotype consisting of GH, prolactin, TSH, LH, and FSH deficiency; abnormal pituitary morphology; and limited neck rotation. Objective: The objective of the study was to determine the frequency and nature of LHX3 mutations in patients with isolated GH deficiency or combined pituitary hormone deficiency (CPHD) and characterize the molecular consequences of mutations. Design: The LHX3 sequence was determined. The biochemical properties of aberrant LHX3 proteins resulting from observed mutations were characterized using reporter gene and DNA binding experiments. Patients: The study included 366 patients with isolated GH deficiency or CPHD. Results: In seven patients with CPHD from four consanguineous pedigrees, four novel, recessive mutations were identified: a deletion of the entire gene (del/del), mutations causing truncated proteins (E173ter, W224ter), and a mutation causing a substitution in the homeodomain (A210V). The mutations were associated with diminished DNA binding and pituitary gene activation, consistent with observed hormone deficiencies. Whereas subjects with del/del, E173ter, and A210V mutations had limited neck rotation, patients with the W224ter mutation did not. Conclusions: LHX3 mutations are a rare cause of CPHD involving deficiencies for GH, prolactin, TSH, and LH/FSH in all patients. Whereas most patients have a severe hormone deficiency manifesting after birth, milder forms can be observed, and limited neck rotation is not a universal feature of patients with LHX3 mutations. This study extends the known molecular defects and range of phenotypes found in LHX3-associated diseases.

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A Distal Modular Enhancer Complex Acts to Control Pituitary- and Nervous System-Specific Expression of the LHX3 Regulatory Gene

Molecular Endocrinology ◽

10.1210/me.2011-1252 ◽

2012 ◽

Vol 26 (2) ◽

pp. 308-319 ◽

Cited By ~ 10

Author(s):

Rachel D. Mullen ◽

Soyoung Park ◽

Simon J. Rhodes

Keyword(s):

Nervous System ◽

Pediatric Patients ◽

Regulatory Gene ◽

Nervous System Development ◽

Hormone Deficiency ◽

Pituitary Hormone ◽

Specific Expression ◽

Enhancer Activity ◽

Pituitary Hormone Deficiency ◽

Combined Pituitary Hormone Deficiency

Abstract Lin-11, Isl-1, and Mec-3 (LIM)-homeodomain (HD)-class transcription factors are critical for many aspects of mammalian organogenesis. Of these, LHX3 is essential for pituitary gland and nervous system development. Pediatric patients with mutations in coding regions of the LHX3 gene have complex syndromes, including combined pituitary hormone deficiency and nervous system defects resulting in symptoms such as dwarfism, thyroid insufficiency, infertility, and developmental delay. The pathways underlying early pituitary development are poorly understood, and the mechanisms by which the LHX3 gene is regulated in vivo are not known. Using bioinformatic and transgenic mouse approaches, we show that multiple conserved enhancers downstream of the human LHX3 gene direct expression to the developing pituitary and spinal cord in a pattern consistent with endogenous LHX3 expression. Several transferable cis elements can individually guide nervous system expression. However, a single 180-bp minimal enhancer is sufficient to confer specific expression in the developing pituitary. Within this sequence, tandem binding sites recognized by the islet-1 (ISL1) LIM-HD protein are essential for enhancer activity in the pituitary and spine, and a pituitary homeobox 1 (PITX1) bicoid class HD element is required for spatial patterning in the developing pituitary. This study establishes ISL1 as a novel transcriptional regulator of LHX3 and describes a potential mechanism for regulation by PITX1. Moreover, these studies suggest models for analyses of the transcriptional pathways coordinating the expression of other LIM-HD genes and provide tools for the molecular analysis and genetic counseling of pediatric patients with combined pituitary hormone deficiency.

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Model of pediatric pituitary hormone deficiency separates the endocrine and neural functions of the LHX3 transcription factor in vivo

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1009501108 ◽

2010 ◽

Vol 108 (1) ◽

pp. 173-178 ◽

Cited By ~ 16

Author(s):

Stephanie C. Colvin ◽

Raleigh E. Malik ◽

Aaron D. Showalter ◽

Kyle W. Sloop ◽

Simon J. Rhodes

Keyword(s):

Nervous System ◽

Transcription Factor ◽

Mouse Model ◽

Gene Activation ◽

Premature Termination Codon ◽

Nervous System Development ◽

Hormone Deficiency ◽

Pituitary Hormone ◽

Pituitary Hormone Deficiency

The etiology of most pediatric hormone deficiency diseases is poorly understood. Children with combined pituitary hormone deficiency (CPHD) have insufficient levels of multiple anterior pituitary hormones causing short stature, metabolic disease, pubertal failure, and often have associated nervous system symptoms. Mutations in developmental regulatory genes required for the specification of the hormone-secreting cell types of the pituitary gland underlie severe forms of CPHD. To better understand these diseases, we have created a unique mouse model of CPHD with a targeted knockin mutation (Lhx3 W227ter), which is a model for the human LHX3 W224ter disease. The LHX3 gene encodes a LIM-homeodomain transcription factor, which has essential roles in pituitary and nervous system development in mammals. The introduced premature termination codon results in deletion of the carboxyl terminal region of the LHX3 protein, which is critical for pituitary gene activation. Mice that lack all LHX3 function do not survive beyond birth. By contrast, the homozygous Lhx3 W227ter mice survive, but display marked dwarfism, thyroid disease, and female infertility. Importantly, the Lhx3 W227ter mice have no apparent nervous system deficits. The Lhx3 W227ter mouse model provides a unique array of hormone deficits and facilitates experimental approaches that are not feasible with human patients. These experiments demonstrate that the carboxyl terminus of the LHX3 transcription factor is not required for viability. More broadly, this study reveals that the in vivo actions of a transcription factor in different tissues are molecularly separable.

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Late onset adrenocorticotrope deficiency in combined pituitary hormone deficiency caused by a mutation of the PROP1 gene

Endocrine Abstracts ◽

10.1530/endoabs.56.p721 ◽

2018 ◽

Author(s):

Silvia Paredes ◽

Olinda Marques ◽

Marta Alves

Keyword(s):

Late Onset ◽

Hormone Deficiency ◽

Pituitary Hormone ◽

Pituitary Hormone Deficiency ◽

Combined Pituitary Hormone Deficiency ◽

Prop1 Gene

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Metabolic status of patients with combined pituitary hormone deficiency due to PROP1 mutation

Endocrine Abstracts ◽

10.1530/endoabs.70.aep735 ◽

2020 ◽

Author(s):

Damian Rogoziński ◽

Aleksandra Gilis-Januszewska ◽

Łukasz Kluczyński ◽

Magdalena Godlewska ◽

Alicja Hubalewska-Dydejczyk

Keyword(s):

Metabolic Status ◽

Hormone Deficiency ◽

Pituitary Hormone ◽

Pituitary Hormone Deficiency ◽

Combined Pituitary Hormone Deficiency

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A novel recessive splicing mutation in the POU1F1 gene causing combined pituitary hormone deficiency

Journal of Endocrinological Investigation ◽

10.1007/bf03345736 ◽

2009 ◽

Vol 32 (8) ◽

pp. 653-658 ◽

Cited By ~ 8

Author(s):

Y. Carlomagno ◽

M. Salerno ◽

D. Vivenza ◽

D. Capalbo ◽

M. Godi ◽

...

Keyword(s):

Hormone Deficiency ◽

Pituitary Hormone ◽

Splicing Mutation ◽

Pou1f1 Gene ◽

Pituitary Hormone Deficiency ◽

Combined Pituitary Hormone Deficiency

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MECHANISMS IN ENDOCRINOLOGY: An update in the genetic aetiologies of combined pituitary hormone deficiency

Acta Endocrinologica ◽

10.1530/eje-15-1095 ◽

2016 ◽

Vol 174 (6) ◽

pp. R239-R247 ◽

Cited By ~ 26

Author(s):

Frederic Castinetti ◽

Rachel Reynaud ◽

Alexandru Saveanu ◽

Nicolas Jullien ◽

Marie Helene Quentien ◽

...

Keyword(s):

Transcription Factors ◽

G Protein Coupled Receptors ◽

Hormone Deficiency ◽

Immunoglobulin Superfamily ◽

Pituitary Hormone ◽

Pituitary Hormone Deficiency ◽

Combined Pituitary Hormone Deficiency ◽

Signalling Molecules ◽

Genes Encoding ◽

G Protein Coupled

Over the last 5 years, new actors involved in the pathogenesis of combined pituitary hormone deficiency in humans have been reported: they included a member of the immunoglobulin superfamily glycoprotein and ciliary G protein-coupled receptors, as well as new transcription factors and signalling molecules. New modes of inheritance for alterations of genes encoding transcription factors have also been described. Finally, actors known to be involved in a very specific phenotype (hypogonadotroph hypogonadism for instance) have been identified in a wider range of phenotypes. These data thus suggest that new mechanisms could explain the low rate of aetiological identification in this heterogeneous group of diseases. Taking into account the fact that several reviews have been published in recent years on classical aetiologies of CPHD such as mutations ofPOU1F1orPROP1, we focused the present overview on the data published in the last 5 years, to provide the reader with an updated review on this rapidly evolving field of knowledge.

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