Identification and characterization of cul-3b, a novel hominine CUL-3 transcript variant.
OBJECTIVE
To identify genes related to the human testis development by substrate hybridization technique.


METHODS
A human testis cDNA microarray was constructed and hybridized with probes prepared from human adult and fetal testes and spermatozoa mRNAs by reverse transcription reactions. The differentially expressed genes were sequenced. And a newly identified cullin-3 (CUL-3) transcript variant (designated cul-3b) was bio-informatically analyzed with an online GenBank database. Multi-tissue reverse transcription polymerase chain reaction (RT-PCR) was used to determine the tissue expression profile of cul-3b.


RESULTS
Cul-3b, a novel CUL-3 transcript variant, was identified. The expression level of cul-3b in adult testes was 3.79-fold higher than that in fetal ones. Cul-3b differed from cul-3 (including NM_003590 and AY337761) in the opening reading frame and had three internal ribosomal entry sites IRESes in the 5'-UTR. These led to a 24 amino acid (aa) truncation at N-terminus of CUL-3b as compared with CUL-3 and a more motivated expression pattern of cul-3b under some strict circumstances. Additionally, cul-3b expressed ubiquitously in human tissues according to multi-tissue RT-PCR.


CONCLUSIONS
Cul-3b is a novel transcript variant of CUL-3, which may be important not only for the development of human testis but also for that of other organs.
Lu
Li
L
Key Laboratory of Reproductive Medicine, Nanjing Medical University, Hanzhong Road, Nanjing 210029, China.
Zhou
Zuo-Ming
ZM
Huang
Xiao-Yan
XY
Xu
Min
M
Yin
Lan-Lan
LL
Wang
Hui
H
Xu
Zhi-Yang
ZY
Sha
Jia-Hao
JH
D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics*; D044842:Cullin Proteins / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
C503645:CUL3 protein, human; D018797:Cell Cycle Proteins; D044842:Cullin Proteins; D012333:RNA, Messenger