Infertility with defective spermiogenesis in mice lacking AF5q31, the target of chromosomal translocation in human infant leukemia.
AF5q31 (also called MCEF) was identified by its involvement in chromosomal translocation with the gene MLL (mixed lineage leukemia), which is associated with infant acute lymphoblastic leukemia. Several potential roles have been proposed for AF5q31 and other family genes, but the specific requirements of AF5q31 during development remain unclear. Here, we show that AF5q31 is essential for spermatogenesis. Although most AF5q31-deficient mice died in utero and neonatally with impaired embryonic development and shrunken alveoli, respectively, 13% of AF5q31-deficient mice thrived as wild-type mice did. However, the male mice were sterile with azoospermia. Histological examinations revealed the arrest of germ cell development at the stage of spermiogenesis, and virtually no spermatozoa were seen in the epididymis. AF5q31 was found to be preferentially expressed in Sertoli cells. Furthermore, mutant mice displayed severely impaired expression of protamine 1, protamine 2, and transition protein 2, which are indispensable to compact the haploid genome within the sperm head, and an increase of apoptotic cells in seminiferous tubules. Thus, AF5q31 seems to function as a transcriptional regulator in testicular somatic cells and is essential for male germ cell differentiation and survival. These results may have clinical implications in the understanding of human male infertility.
Urano
Atsushi
A
Institute of Medical Science Division of Hematopoietic Factors, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Endoh
Masaki
M
Wada
Tadashi
T
Morikawa
Yoshihiro
Y
Itoh
Miyuki
M
Kataoka
Yuki
Y
Taki
Tomohiko
T
Akazawa
Hiroshi
H
Nakajima
Hideaki
H
Komuro
Issei
I
Yoshida
Nobuaki
N
Hayashi
Yasuhide
Y
Handa
Hiroshi
H
Kitamura
Toshio
T
Nosaka
Tetsuya
T
D000818:Animals; D017209:Apoptosis / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D018390:Gene Targeting; D011495:Histone-Lysine N-Methyltransferase; D006801:Humans; D007223:Infant; D007248:Infertility, Male / Q000235:genetics*; D007938:Leukemia / Q000235:genetics*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D051788:Myeloid-Lymphoid Leukemia Protein; D011519:Proto-Oncogenes / Q000235:genetics*; D013091:Spermatogenesis / Q000235:genetics*; D013094:Spermatozoa / Q000502:physiology; D013737:Testis / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D035602:Transcriptional Elongation Factors; D014178:Translocation, Genetic
C503581:Aff4 protein, mouse; D004268:DNA-Binding Proteins; C497422:KMT2A protein, human; D014157:Transcription Factors; D035602:Transcriptional Elongation Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase; C497423:Kmt2a protein, mouse