Ubiquitin C-terminal hydrolase-L1 (Uch-L1) correlates with gonadal transformation in the rice field eel.
The ubiquitin-proteasome pathway is crucial for a variety of biological processes, including spermatogenesis. Ubiquitin C-terminal hydrolase-L1 (Uch-L1) is thought to associate with monoubiquitin to control ubiquitin levels. Here, we report the identification of Uch-L1 cDNA from the testis of the rice field eel, a natural sex reversal vertebrate, by using cDNA microarray analysis. Uch-L1 encodes a protein of 220 amino acids that shows high homology to Uch-L1 of vertebrates, especially fish species. Both mRNA and protein are mainly expressed in testis, ovotestis and ovary, as well as in the brain. Immunohistochemistry analysis revealed differential expression of Uch-L1 in three kinds of gonads. In the ovary, expression of Uch-L1 was observed mainly in the developing ovary and slightly in the mature ovary. In ovotestis during the intersex stage, Uch-L1 was expressed in the male gonad epithelium and degraded ovary. In testis, expression was observed in developing germ cells, including spermatogonia and spermatocytes. Furthermore, Uch-L1 was upregulated during gonadal transformation, especially from the beginning of the intersex stage onwards. Native-PAGE showed that Uch-L1 underwent dimerization and oligomerization in gonads, and that the relative level of dimerization/oligomerization decreased during gonadal transformation. Simultaneously, ubiquitin polypeptide expression was upregulated during this process. These results suggest that Uch-L1, via the ubiquitin-proteasome system, may play an important role not only in gametogenesis, but also in the gonadal transformation process in the rice field eel.
Sun
Jinhua
J
Department of Genetics and Center for Developmental Biology, College of Life Sciences, Wuhan University, China.
Shang
Xuan
X
Tian
Yihao
Y
Zhao
Wei
W
He
Yan
Y
Chen
Ke
K
Cheng
Hanhua
H
Zhou
Rongjia
R
D000818:Animals; D001483:Base Sequence; D001704:Biopolymers; D015152:Blotting, Northern; D015153:Blotting, Western; D017931:DNA Primers; D004524:Eels / Q000502:physiology*; D004591:Electrophoresis, Polyacrylamide Gel; D019143:Evolution, Molecular; D005260:Female; D005854:Germ Cells / Q000201:enzymology; D006066:Gonads; D057850:Hermaphroditic Organisms; D047468:Immunoprecipitation; D008297:Male; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019849:Sex Determination Processes / Q000201:enzymology*; D025801:Ubiquitin / Q000378:metabolism; D043222:Ubiquitin Thiolesterase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
D001704:Biopolymers; D017931:DNA Primers; D025801:Ubiquitin; D043222:Ubiquitin Thiolesterase