Expression and localization of RAP250 mRNA in rat ovary: possible implications in follicular development and ovulation.
The expression levels of nuclear receptor coregulators in specific tissue compartments and cells are thought to influence the expression of hormone-responsive genes involved in metabolism, development, and reproduction. RAP250 is a novel nuclear receptor coactivator highly expressed in brain and reproductive organs. To investigate the possible involvement of RAP250 in tissue-specific regulation of ovarian function, untreated immature, pregnant mare's serum gonadotropin luteinizing hormone (PMSG-LH)-primed, cycling, and pregnant rat models were used to study the localization and expression of RAP250 mRNA in rat ovary by in situ hybridization (ISH) and reverse transcriptase polymerase chain reaction (RT-PCR). The results showed that RAP250 mRNA was primarily localized to granulosa cells of healthy follicles in immature, cycling, and pregnant rats and increased during PMSG-induced follicular development. In the preovulatory and ovulatory follicles from the LH-primed rats of 48-h post-PMSG administration, the signals for RAP250 mRNA increased further and remained high until early luteal formation. Only a subset of corpora lutea during diestrus 1, diestrus 2, and initiation of pregnancy was weakly positive, and atretic follicles were largely negative. The RT-PCR results confirmed the presence of RAP250 mRNA in the rat ovary and strengthen the data from ISH. These findings suggest that RAP250 may play potential roles in follicular development and ovulation.
Liu
Dong-Lin
DL
tnstitute of Zoology, Chinese Acadnmy of Sciences, Beijing PR China.
Li
Qing-Lei
QL
Lin
Hai-Yan
HY
Liu
Wen-Zhe
WZ
Wang
Hong-Mei
HM
Zhang
Xuan
X
Zhu
Cheng
C
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000502:physiology; D017403:In Situ Hybridization; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D056918:Nuclear Receptor Coactivators; D006080:Ovarian Follicle / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012689:Sequence Homology, Nucleic Acid
D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; C486560:Ncoa6 protein, rat; D056918:Nuclear Receptor Coactivators; D012333:RNA, Messenger