Testis Development

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Introduction

Historic testis drawing

The male gonad is the testis. The initial difference in male and female gonad development are dependent on testis-determining factor (TDF) the protein product of the Y chromosome SRY gene. Recent studies have indicated that additional factors may also be required for full differentiation. The seminiferous tubules are considered the parenchyma of the testis. Within the developing testis the three main differentiating cell types are: gamete forming cells (spermatogonia), support cells (Sertoli cells) and hormone secreting cells (Leydig or interstitial cells).


In humans postnatally, at approximately 2 months of age, primordial germ cells (gonocytes) are replaced by adult dark (Ad) and pale (Ap) spermatogonia that make up the spermatogonial stem cell (SSC) population that at puberty will commence differentiation into spermatozoa.


Genital Links: Introduction | Lecture - Medicine | Lecture - Science | Online Practical | Primordial Germ Cell | Meiosis | Female | Ovary | Oocyte | Uterus | Vagina | Reproductive Cycles | Menstrual Cycle | Male | Testis | Spermatozoa | Prostate | Genital Movies | Abnormalities | Assisted Reproductive Technology | Puberty | Category:Genital
Historic Embryology - Genital
1902 The Uro-Genital System | 1912 Urinogenital Organ Development | 1921 Urogenital Development | 1921 External Genital Development | Historic Disclaimer

Some Recent Findings

Gadd45g and Sex Determination Model[1]
  • Gadd45g is essential for primary sex determination, male fertility and testis development[1] "In humans and most mammals, differentiation of the embryonic gonad into ovaries or testes is controlled by the Y-linked gene SRY. Here we show a role for the Gadd45g protein in this primary sex differentiation. ...The molecular cause of the sex reversal was the failure of Gadd45g(-/-) XY gonads to achieve the SRY expression threshold necessary for testes differentiation, resulting in ovary and Müllerian duct development. These results identify Gadd45g as a candidate gene for male infertility and 46,XY sex reversal in humans."
  • Prenatal testosterone and dihydrotestosterone exposure disrupts ovine testes development [2] "Androgens play important roles during the first trimester of intrauterine life, coinciding with genital tract differentiation, during virilization and maintenance of secondary male characteristics and during initiation of spermatogenesis. ... Findings from this study demonstrate that exposure to excess testosterone/5α-dihydrotestosterone (DHT) during male fetal sexual differentiation have differential effects on post-pubertal testicular size, seminiferous tubule size and function, sperm motility, and testosterone concentrations." Sheep Development
  • Oestrogen blocks the nuclear entry of SOX9 in the developing gonad of a marsupial mammal.[3] "We have uncovered a mechanism by which oestrogen can regulate gonadal development through the nucleocytoplasmic shuttling of SOX9. This may represent an underlying ancestral mechanism by which oestrogen promotes ovarian development in the gonads of nonmammalian vertebrates. Furthermore, oestrogen may retain this function in adult female mammals to maintain granulosa cell fate in the differentiated ovary by suppressing nuclear translocation of the SOX9 protein."
  • The evolutionary history of testicular externalization and the origin of the scrotum[4] "We mapped four character states reflecting the position of testes and presence of scrotum onto recent mammalian phylogeny. Our results are interpreted as follows: as to the presence of testicondy in Monotremata and most of Atlantogenata, which represent the basal group of all eutherians, we argue that primary testicondy represents a plesiomorphic condition for Eutheria as well as for all mammals. This is in opposition to the previous hypothesis of Werdelin and Nilsonne that the scrotum may have evolved before the origin of mammals and then repeatedly disappeared in many groups including monotremes. We suggest that the scrotum evolved at least twice during the evolutionary history of mammals, within Marsupialia and Boreoeutheria, and has subsequently been lost by many groups; this trend is especially strong in Laurasiatheria. We suggest that the recent diversity in testicular position within mammals is the result of multiple selection pressures stemming from the need to provide conditions suitable for sperm development and storage, or to protect the male gonads from excessive physical and physiological disturbance."
  • FGF signaling directs a center-to-pole expansion of tubulogenesis in mouse testis differentiation.[5] "These observations imply that center-to-pole FGF9 diffusion directs a poleward expansion of testiculogenic programs along the anteroposterior axis of developing XY gonads."
More recent papers
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This table shows an automated computer PubMed search using the listed sub-heading term.
  • Therefore the list of references do not reflect any editorial selection of material based on content or relevance.
  • References appear in this list based upon the date of the actual page viewing.

References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability.

Links: References | Discussion Page | Pubmed Most Recent


Search term: Testis Embryology

Satomi S Tanaka, Ryuichi Nishinakamura Regulation of male sex determination: genital ridge formation and Sry activation in mice. Cell. Mol. Life Sci.: 2014; PMID:25139092 Jian Shen, Wen Chen, Binbin Shao, Yujuan Qi, Zhengrong Xia, Fuqiang Wang, Lei Wang, Xuejiang Guo, Xiaoyan Huang, Jiahao Sha Lamin A/C proteins in the spermatid acroplaxome are essential in mouse spermiogenesis. Reproduction: 2014; PMID:25118303 Mai Thi Nhu Tran, Junko Tanaka, Michito Hamada, Yuka Sugiyama, Shota Sakaguchi, Megumi Nakamura, Satoru Takahashi, Yoshihiro Miwa In Vivo image Analysis Using iRFP Transgenic Mice. Exp. Anim.: 2014, 63(3);311-319 PMID:25077761 Julio Castañeda, Pavol Genzor, Godfried W van der Heijden, Ali Sarkeshik, John R Yates, Nicholas T Ingolia, Alex Bortvin Reduced pachytene piRNAs and translation underlie spermiogenic arrest in Maelstrom mutant mice. EMBO J.: 2014; PMID:25063675 Fereshteh Khaneshi, Ozra Nasrolahi, Shahriar Azizi, Vahid Nejati Sesame effects on testicular damage in streptozotocin-induced diabetes rats. Avicenna J Phytomed: 2013, 3(4);347-55 PMID:25050292

Movies

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 ‎‎Testis
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 ‎‎Male External
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 ‎‎Testis Descent
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Links: Movies

Development Overview

Male urogenital development (stage 22)
Fetal gonad retinoid receptor expression[6]

Sex Determination

  • Humans (week 5-6)
  • Germ cells migrate into gonadal ridge
  • Gonads (male/female) identical at this stage, Indifferent

Gonad Development

  • dependent on sex chromosome
  • Y testes
  • No Y ovary

SRY

SRY protein (Testes determining factor, TDF) binds DNA Transcription factor, Bends DNA 70-80 degrees

Internal Genital Organs

  • All embryos form paired
  • Mesonephric duct, see kidney development
  • Paramesonephric duct, Humans 7th week Invagination of coelomic epithelium Cord grows and terminates on urogenital sinus
  • Male Gonad (testes) secretes Mullerian duct inhibitory factor (MDIF) which causes regression of paramesonephric duct
  • Male Gonad (testes) secretes Testosterone which retains mesonephric duct

External Genital Organs

  • All embryos initially same (indifferent)
  • Testosterone differentiates male

Week 8

Carnegie stage 22

Stage 22 image 302.jpg Stage 22 image 301.jpg

Developing testis is shown to the centre right. These images show the position, size and histological development of the testis in week 8 of human development (Carnegie stage 22, last embryonic week).

Testis Links: Testis - labeled overview | Testis - unlabeled overview | Testis - unlabeled detail | Testis - labeled detail | Testis Development | Carnegie stage 22 | Movie - Urogenital stage 22

Sertoli Cells

Adult Seminiferous tubule showing spermatozoa developmental stages
Adult Seminiferous tubule showing spermatozoa developmental stages
Gonadal supporting cell development
Gonadal supporting cell development

These cells provide support for spermatozoa development within the seminiferous tubule. They are derived from the coelomic epithelium, along with other testis somatic cells.[7] Their differentiation is regulated by the presence of a Y chromosome and in turn regulates Leydig cell differentiation. Sertoli cells direct testis morphogenesis, organizing testis cord formation, establishing testis vasculature and inducing differentiation of peritubular myoid cells and fetal Leydig cells. At puberty the immature Sertoli cells cease to proliferate and differentiate.

Sertoli cell functions include:

  • regulation of spermatogenesis through endocrine FSH and testosterone
  • regulation of the intratubular and intercellular environment adluminal to the tight junctional complexes
    • meiotic and post-meiotic germ cells are sequestered by Sertoli-Sertoli junctional complexes
  • generate adluminal compartment isolated from both serum and lymph
  • attachment of germ cells through unique intermediate filament (desmosome-like junctions) and microfilament (actin- ectoplasmic specializations, ESs) junctions[8]
    • to prevent premature sloughing of immature germ cells from the seminiferous epithelium
    • desmosome-like junctions are initially present (up to step 8 spermatids)
    • ectoplasmic specializations then replace this junction (in step 8 spermatids)

(see also review[9])

Ultrastructural description of human Sertoli cells[10]

  • 7 weeks - first morphologically recognised in testicular cords, organised as primordial germ cells surrounded by pre-Sertoli cells.
  • 7 to 8 weeks - basal lamina of the cords becomes distinguishable, pre-Sertoli cells the rough endoplasmic reticulum develops.
  • 14 to 20 weeks - pre-Sertoli cells maintain their general morphology whereas the most significant change is the maximum development of Leydig cells.

Molecular factors:

  • Follicle Stimulating Hormone (FSH) -> Krüppel-like factor 4 (KLF4)
  • Krüppel-like factor 4 (KLF4) - zinc finger transcription factor, terminal differentiation of epithelial cells.
  • Epidermal Growth Factor (EGF)
  • Transforming Growth Factor-beta (TGFbeta)

Leydig Cells

Seminiferous tubule cross-section and supporting cells

Interstitial or Leydig cells, named after german zoologist Franz von Leydig (1821 - 1908).

These cells produce the male testicular androgens and have a role during life prenatally (fetal) and postnatally during puberty onward.

Fetal Leydig Cells

Have a hormonal role in male genitalia differentiation and are lost postnatally. These cells arise approximately at 6 weeks (human) and 12.5 dpc (mouse) and there appears to be differences in hormonal sensitivity between the species. Their initial differentiation requires both luteinizing hormone (LH) and adrenocorticotrophic hormone (ACTH) and therefore normal pituitary development.

Activin A - acts upon Sertoli cells to promote their embryonic proliferation[11]

(More? Endocrine - Pituitary Development)

Adult Leydig Cells

Have a hormonal role in puberty, secondary sex characteristics and sexual maturation. Their initial differentiation from peritubular mesenchymal cells does not require gonadotropin, but development and function are dependent upon luteinizing hormone (LH).

The cells differentiate with three discrete stages (newly formed, immature, mature) leading to a decrease in proliferation and increasing testosterone biosynthetic capacity. Insulin-like growth factor I (IGF-I) stimulates proliferation of immature cells and promotes their maturation. Testosterone and estrogen inhibit the process of precursor cell differentiation and may be responsible for the cessation of proliferation in the adult Leydig cells.

Leydig Cell Electron Micrographs
Leydig cell PMID13693345 EM02.jpg Leydig cell PMID13693345 EM03.jpg
Low power EM High power EM

EM images above from historic study of the opossum testis.[12]

Peritubular Myoid Cells

These cells surround the seminiferous tubules and express androgen receptors from fetal life through to adulthood.

Epididymis

Adult Epididymis Histology
Mouse postnatal epididymis development[13]

Both the ductus epididymis and ductus deferens differentiate from the mesonephric duct (Wollfian duct) elongation (cell proliferation). In the case of the epididymis, elongation also is associated with extensive coiling, the adult human epididymis about 6 metres in length (mouse 1m, rat 3m). Embryonic growth is regulated by androgens, members of the PCP pathway, and inhibin beta A. While postnatally androgens and other growth factors may have roles in final maturation. (see review[14]) The ductus epididymis is lined by a very tall pseudostratified columnar epithelium, consisting of principal cells with long stereo cilia.

Following puberty, the epididymis is involved in maturation of the spermatozoa released from the seminiferous tubules and their storage.

  • middle segment - site of final functional maturation of the spermatozoa.
  • terminal segment - site of storage of the mature spermatozoa.

Anatomically the adult epididymis consists of 3 regions:

  • body or central portion.
  • head (globus major) upper enlarged extremity.
  • tail (globus minor) lower pointed extremity, continuous with the ductus deferens (vas deferens).

The head is intimately connected with the upper end of the testis by means of the efferent ductules of the gland; the tail is connected with the lower end by cellular tissue, and a reflection of the tunica vaginalis (tunica vaginalis propria testis) the serous covering of the testis.

The lateral surface, head and tail of the epididymis are free and covered by the serous membrane; the body is also completely invested by it, excepting along its posterior border; while between the body and the testis is a pouch, named the sinus of the epididymis (digital fossa). The epididymis is connected to the back of the testis by a fold of the serous membrane.

Testis Descent

Testis descent is thought to have 2 phases:

  1. transabdominal descent - dependent on insulin-like hormone 3 (INSL3).
  2. inguinoscrotal descent - dependent on androgens.

The regulation of testis descent is still being investigated and several different factors have been identified that may have roles in descent. The first stage of testicular descent occurs 10–15 weeks of gestation with the testes moving to the inguinal region.

The gubernaculum (gubernaculum Hunteri) is the caudal inguinoscrotal ligament that connects the testis to the lower abdomen. The cranial suspensory ligament (mesonephric ligament) is the cranial ligament that connects the tesitis to the posterior abdominal wall.

  • Insulin-like factor 3 (INSL3, relaxin-like factor) from fetal leydig cells acting through its receptor (Rxfp2) and BMP and WNT signaling pathways to promote testis descent.
  • Calcitonin gene-related peptide (CGRP) from genitofemoral nerve suggested to mediate the inguinoscrotal testicular descent.
  • Epidermal growth factor (EGF) may promote by activating the androgen responsive systems.


Testis-descent start.jpg Testis-descent end.jpg
Testis 001 icon.jpg
 ‎‎Testis Descent
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Before Descent End of Descent Testis Descent Movie



Links: OMIM - INSL3

Cryptorchidism

Cryptorchidism
Newborn - cryptorchidism normal birthweight[15]
  • abnormality of either unilateral or bilateral testicular descent, occurring in up to 30% premature and 3-4% term males.
  • Descent may complete postnatally in the first year, failure to descend can result in sterility.

Testis descent is thought to have 2 phases:

  1. transabdominal descent - dependent on insulin-like hormone 3 (INSL3).
  2. inguinoscrotal descent - dependent on androgens.

Management of cryptorchidism in children: guidelines.[16] "Cryptorchidism is best diagnosed clinically, and treated by surgical orchiopexy at age 6-12 months, without a routine biopsy. If no testis is palpable, or if other signs of hypovirilisation such as hypospadias are present, the chromosomal sex and hormonal status must be assessed. Laparoscopy is the best way of diagnosing and managing intra-abdominal testes."

Anorchia

Clinical term for (embryonic testicular regression, vanishing testis syndrome) the absence of testes in a 46,XY individual with a male phenotype. Rare abnormality with an incidence of about 1 in 20,000 male births, and occurs more frequently with cryptorchidism (1 in 177 cases).

A recent study has identified undetectable plasma concentrations of anti-Müllerian hormone (AMH) and inhibin B and an elevated plasma FSH, together with 46,XY complement are sufficient for diagnosis of anorchia. Genetic analysis showed that NR5A1 and other genes (INSL3, SRY, LGR8 , MAMLD1) implicated in gonadal development and testicle descent were also not mutated.[17]

Puberty

Male testosterone and AMH level graph.jpg

Human Male Testosterone and Anti-Müllerian Hormone (AMH) relative levels[18]

  • AMH production by Sertoli cells .
  • Testosterone production by Leydig cells.

In humans at puberty, hormonal and morphological changes occur within the gonad and other systems (secondary sex characteristics). Within the testis the immature Sertoli cells cease to proliferate and differentiate. Spermatogonium proliferate and spermatogenesis begins, and it takes about 70 days for cells to mature from the diploid spermatogonium to a primary spermatocyte. This maturation occurs in waves along the seminiferous tubules.

Links: Puberty Development

Blood-Testis Barrier

Within the testis seminiferous tubules the Sertoli cells located near the basement membrane act as an initial cellular barrier with many functions, but often described as forming a "blood-testis barrier". (see review[19]

Functions:

  • prevent substances reaching the developing spermatozoa (through drug transporters)
  • establish a basal and adluminal (apical) compartment (specialized microenvironment)
  • provide an immunological privilege status of the testis (anti-sperm antibodies are not developed)

Histology

Testis Histology Links: Testis Development | Spermatozoa Development | Histology

Human (young): overview labeled | overview unlabeled | convoluted seminiferous tubules x10 | x40 | x40 | tunica albuginea x20
Human (adult): overview x2 | convoluted seminiferous tubules labeled | x10 | x20 | x40 | x40 | epididymis ductulus efferens | ductus epididymidis | epithelium | overview x4 | x10 | x20 | x40 | ductus deferens labeled overview | epithelium | overview x2 | x10 | x40
Human spermatozoa: x20 | x40 | x100
Human stage 22:
Testis Links: Testis - labeled overview | Testis - unlabeled overview | Testis - unlabeled detail | Testis - labeled detail | Testis Development | Carnegie stage 22 | Movie - Urogenital stage 22
Rabbit: convoluted seminiferous tubules x20 | x100
Mouse: postnatal epididymis | 14 days postnatal | 33 days postnatal | 45 days postnatal | 2 months postnatal
Links: Spermatozoa Histology | Histology Stain H&E | Histology Stains

Molecular

Sry

  • Y chromosome gene for a transcription factor
  • member of the high mobility group (HMG)-box family of DNA binding proteins
  • human - 204 amino acid protein [20]
Links: OMIM - Sry

Sox9

  • autosomal transcription factor
  • Development of XY females - presence of only a single functional copy of the transcription factor encoding genes SOX9, SF1, or WT1 (Note- not all XY humans are sex-reversed if only a single copy of a normal SF1 or WT1 allele is present)
  • A nuclear export signal within the high mobility group domain regulates the nucleocytoplasmic translocation of SOX9 during sexual determination[21]

Other roles

  • Cartilage - essential for chondrocyte differentiation
  • Hearing - otic placode formation, maintenance of progenitors in the otic epithelium


Links: Sox9 | Cartilage Development | Inner Ear Development

Fog2

  • transcription factor, named Friend of Gata2
  • human - (8q23) 1,151 amino acid nuclear protein that contains 8 zinc finger motifs[22]
  • dosage critical for fetal testis development in mice[23]
Links: OMIM - Fog2

Gadd45g

Gadd45g and Sex Determination Model[1]

Growth Arrest- And Dna Damage-Inducible Gene (GADD45, GAMMA; GADD45G)

A Recent mouse study[1] has shown that Gadd45g protein has a role in primary sex differentiation. Knockout mice (Gadd45g(-/-) XY gonads) resulted in a a sex reversal.


Links: OMIM - Gadd45g

Gata4

  • transcription factor
  • dosage critical for fetal testis development in mice[23]

Eif2s3y

References

  1. 1.0 1.1 1.2 1.3 Heiko Johnen, Laura González-Silva, Laura Carramolino, Juana Maria Flores, Miguel Torres, Jesús M Salvador Gadd45g is essential for primary sex determination, male fertility and testis development. PLoS ONE: 2013, 8(3);e58751 PMID:23516551
  2. Charles L Bormann, Gary D Smith, Vasantha Padmanabhan, Theresa M Lee Prenatal testosterone and dihydrotestosterone exposure disrupts ovine testicular development. Reproduction: 2011, 142(1);167-73 PMID:21493716
  3. Andrew J Pask, Natalie E Calatayud, Geoff Shaw, William M Wood, Marilyn B Renfree Oestrogen blocks the nuclear entry of SOX9 in the developing gonad of a marsupial mammal. BMC Biol.: 2010, 8;113 PMID:20807406 | PMC2940779 | BMC Biol.
  4. Karel Kleisner, Richard Ivell, Jaroslav Flegr The evolutionary history of testicular externalization and the origin of the scrotum. J. Biosci.: 2010, 35(1);27-37 PMID:20413907 | PDF
  5. Ryuji Hiramatsu, Kyoko Harikae, Naoki Tsunekawa, Masamichi Kurohmaru, Isao Matsuo, Yoshiakira Kanai FGF signaling directs a center-to-pole expansion of tubulogenesis in mouse testis differentiation. Development: 2010, 137(2);303-12 PMID:20040496
  6. Andrew J Childs, Gillian Cowan, Hazel L Kinnell, Richard A Anderson, Philippa T K Saunders Retinoic Acid signalling and the control of meiotic entry in the human fetal gonad. PLoS ONE: 2011, 6(6);e20249 PMID:21674038
  7. J Karl, B Capel Sertoli cells of the mouse testis originate from the coelomic epithelium. Dev. Biol.: 1998, 203(2);323-33 PMID:9808783
  8. Ilona A Kopera, Barbara Bilinska, C Yan Cheng, Dolores D Mruk Sertoli-germ cell junctions in the testis: a review of recent data. Philos. Trans. R. Soc. Lond., B, Biol. Sci.: 2010, 365(1546);1593-605 PMID:20403872
  9. M D Griswold Interactions between germ cells and Sertoli cells in the testis. Biol. Reprod.: 1995, 52(2);211-6 PMID:7711190 | Biol Reprod.
  10. R Heyn, S Makabe, P M Motta Ultrastructural morphodynamics of human Sertoli cells during testicular differentiation. Ital J Anat Embryol: 2001, 106(2 Suppl 2);163-71 PMID:11732573
  11. Denise R Archambeault, Humphrey Hung-Chang Yao Activin A, a product of fetal Leydig cells, is a unique paracrine regulator of Sertoli cell proliferation and fetal testis cord expansion. Proc. Natl. Acad. Sci. U.S.A.: 2010, 107(23);10526-31 PMID:20498064 |http://www.pnas.org/content/107/23/10526.long PNAS]
  12. A K CHRISTENSEN, D W FAWCETT The normal fine structure of opossum testicular interstitial cells. J Biophys Biochem Cytol: 1961, 9;653-70 PMID:13693345
  13. Ida Björkgren, Lauri Saastamoinen, Anton Krutskikh, Ilpo Huhtaniemi, Matti Poutanen, Petra Sipilä Dicer1 ablation in the mouse epididymis causes dedifferentiation of the epithelium and imbalance in sex steroid signaling. PLoS ONE: 2012, 7(6);e38457 PMID:22701646 | PLoS One.
  14. Barry T Hinton, Maureen M Galdamez, Ann Sutherland, Daniela Bomgardner, Bingfang Xu, Rana Abdel-Fattah, Ling Yang How do you get six meters of epididymis inside a human scrotum? J. Androl.: 2011, 32(6);558-64 PMID:21441421 | J. Androl.
  15. H E Virtanen, J Toppari Epidemiology and pathogenesis of cryptorchidism. Hum. Reprod. Update: 2007, 14(1);49-58 PMID:18032558 | Hum Reprod Update.
  16. Christophe Gapany, Peter Frey, Françoise Cachat, Françoise Gudinchet, Patrice Jichlinski, Blaise-Julien Meyrat, Pascal Ramseyer, Gérald Theintz, Bernard Burnand Management of cryptorchidism in children: guidelines. Swiss Med Wkly: 2008, 138(33-34);492-8 PMID:18726735
  17. Brauner R, Neve M, Allali S, Trivin C, Lottmann H, Bashamboo A, McElreavey K. Clinical, biological and genetic analysis of anorchia in 26 boys. PLoS One. 2011;6(8):e23292. Epub 2011 Aug 10. PMID 21853106 PLoS One.
  18. Rodolfo Rey Anti-Müllerian hormone in disorders of sex determination and differentiation. Arq Bras Endocrinol Metabol: 2005, 49(1);26-36 PMID:16544032 | Arq Bras Endocrinol Metabol.
  19. Linlin Su, Dolores D Mruk, C Yan Cheng Drug transporters, the blood-testis barrier, and spermatogenesis. J. Endocrinol.: 2011, 208(3);207-23 PMID:21134990 | J Endocrinol.
  20. H Su, Y F Lau Identification of the transcriptional unit, structural organization, and promoter sequence of the human sex-determining region Y (SRY) gene, using a reverse genetic approach. Am. J. Hum. Genet.: 1993, 52(1);24-38 PMID:8434602
  21. Stephan Gasca, Joaquin Canizares, Pascal De Santa Barbara, Catherine Mejean, Francis Poulat, Philippe Berta, Brigitte Boizet-Bonhoure A nuclear export signal within the high mobility group domain regulates the nucleocytoplasmic translocation of SOX9 during sexual determination. Proc. Natl. Acad. Sci. U.S.A.: 2002, 99(17);11199-204 PMID:12169669 | PMC123233 | PNAS
  22. M Holmes, J Turner, A Fox, O Chisholm, M Crossley, B Chong hFOG-2, a novel zinc finger protein, binds the co-repressor mCtBP2 and modulates GATA-mediated activation. J. Biol. Chem.: 1999, 274(33);23491-8 PMID:10438528
  23. 23.0 23.1 Gerrit J Bouma, Linda L Washburn, Kenneth H Albrecht, Eva M Eicher Correct dosage of Fog2 and Gata4 transcription factors is critical for fetal testis development in mice. Proc. Natl. Acad. Sci. U.S.A.: 2007, 104(38);14994-9 PMID:17848526 PMC1986601 | PNAS


Reviews

Terje Svingen, Peter Koopman Building the mammalian testis: origins, differentiation, and assembly of the component cell populations. Genes Dev.: 2013, 27(22);2409-26 PMID:24240231

Barry T Hinton, Maureen M Galdamez, Ann Sutherland, Daniela Bomgardner, Bingfang Xu, Rana Abdel-Fattah, Ling Yang How do you get six meters of epididymis inside a human scrotum? J. Androl.: 2011, 32(6);558-64 PMID:21441421 | J. Androl.

Articles

Elena M Kaftanovskaya, Shu Feng, Zaohua Huang, Yingchun Tan, Agustin M Barbara, Sukhjinder Kaur, Anne Truong, Ivan P Gorlov, Alexander I Agoulnik Suppression of insulin-like3 receptor reveals the role of β-catenin and Notch signaling in gubernaculum development. Mol. Endocrinol.: 2011, 25(1);170-83 PMID:21147849

J B Stukenborg, E Colón, O Söder Ontogenesis of testis development and function in humans. Sex Dev: 2010, 4(4-5);199-212 PMID:20664245

John M Hutson, Adam Balic, Tamara Nation, Bridget Southwell Cryptorchidism. Semin. Pediatr. Surg.: 2010, 19(3);215-24 PMID:20610195

Ibrahim M Adham, Alexander I Agoulnik Insulin-like 3 signalling in testicular descent. Int. J. Androl.: 2004, 27(5);257-65 PMID:15379965


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Cite this page: Hill, M.A. (2014) Embryology Testis Development. Retrieved August 27, 2014, from https://php.med.unsw.edu.au/embryology/index.php?title=Testis_Development

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