Published-Ahead-of-Print January 24, 2007, DOI:10.2164/jandrol.106.001560
Journal of Andrology, Vol. 28, No. 4, July/August 2007
Copyright © American Society of Andrology
DOI: 10.2164/jandrol.106.001560
Expression and Possible Functions of a Novel Gene SPATA12 in Human Testis
LI DAN*,
,
YANG LIFANG
AND
LU GUANGXIU
From the * Institute of Life Science and
Biotechnology, Hunan University, Changsha, China;
Institute of Reproductive and Stem Cell
Engineering, Central South University, Changsha, China; and
Cancer Research Institute, Xiangya School of
Medicine, Central South University, Changsha, China.
|
Correspondence to: Prof Lu Guangxiu, Reproductive and Stem Cell Engineering,
Central South University, Changsha, China (e-mail:
lgxdirector{at}sina.com);
or Dr Li Dan, Institute of Life Science and Biotechnology, Hunan University,
Changsha, China (e-mail:
leedanie{at}tom.com). |
In our previous study, a novel human testis-specific gene,
SPATA12, was identified using the digital differential display
program. In the current study, both SPATA12 mRNA and protein levels
in the developmental stage of the testis were detected by SYBR real-time
reverse transcriptase polymerase chain reaction and Western blot. A high level
of SPATA12 gene expression was observed in normal adult testis but
was completely absent in fetal testis. Both in situ hybridization and
immunohistochemical analysis showed that SPATA12 was expressed in
seminiferous tubules of adult testismore precisely in spermatocytes,
spermatids, and spermatozoabut there was no expression in Sertoli and
Leydig cells. These results showed that SPATA12 is a stage-specific
and germ cellspecific gene, which suggests that it must be involved in
the development of testicular maturation. It was also found that the
expression level of SPATA12 mRNA in the testes of infertile men was
associated with the amount and density of germ cells. With a decrease in the
number of germ cells, the expression of SPATA12 mRNA was lower. In
addition, the signal in the testes of patients with cryptorchidism or Sertoli
cell only syndrome was not detected. Flow cytometry analysis of
SPATA12 in human HeLa cells and mouse GC-1 spg germ cells indicated
that the expression of the SPATA12 gene may delay the progression of
G1 to S in the cell cycle. SPATA12 was also shown to be
lost in testicular germ cell tumors both at the level of transcription and
translation. We hypothesized that the putative function of SPATA12 is
to maintain the cell in a differentiated state and/or to suppress cell
proliferation.
Key words: Germ cell specific, stage specific, spermatogenesis
Copyright © 2007 by The American Society of Andrology.