Three Different Turkey Luteinizing Hormone Receptor (tLH-R) Isoforms II: Characterization of Differentially Regulated tLH-R Messenger Ribonucleic Acid Isoforms in the Ovary

Abstract

We have recently characterized three different, alternatively spliced, partial turkey LH receptor (tLH-R) cDNA isoforms by the combination of reverse transcription-polymerase chain reaction (RT-PCR) and 5'- and 3'-rapid amplification of cDNA ends. The first cDNA (intact form: tLH-R(intact)) showed 98% and 72-75% similarity with chicken and mammalian LH receptor sequences, respectively. The other two cloned cDNA isoforms (insertion and truncated forms: tLH-R(insert) and tLH-R(trunc)) could encode truncated soluble protein isoforms that lack the transmembrane region. Northern blot analysis detected two transcripts of 3.0 kilobases (kb) (tLH-R(intact)) and 1.5 kb (tLH-R(trunc)) in the turkey ovary but could not discriminate a third alternatively spliced transcript (tLH-R(insert)) due to the small 86-base pair difference in the size range of approximately 3.0-kb mRNAs. But with the combination of RNase protection assay, RT-PCR, and Northern blot analysis, three different alternatively spliced tLH-R mRNA isoforms were quantified. Differential expression of the tLH-R mRNA isoforms was demonstrated in ovarian stromal tissue during various reproductive stages and in the theca and granulosa layer through follicular development. To gain a better understanding of the physiological significance of the three different tLH-R isoforms, total RNA from the theca layer through follicular development after prolactin (PRL) treatment was analyzed by RT-PCR. PRL treatment for 8-14 days significantly increased the steady-state levels of total tLH-R mRNAs, including tLH-R(insert) and tLH-R(trunc) mRNAs, compared to those in nontreated controls. In contrast, the steady-state levels of tLH-R(intact) mRNA during the same period was not significantly changed when compared to that in nontreated controls. The present study shows that tLH-R transcripts are alternatively spliced in a tissue-specific manner in the turkey and that the mechanism may, in part, be controlled hormonally.

Prior Experience with Photostimulation Enhances Photo-Induced Reproductive Response in Female House Finches

“…Therefore, the lack of an effect of photo-experience on the LH response to photostimluation suggests that LH may not play a direct role in the physiological mechanisms underlying age-related variation in early reproductive development. However, as the up-regulation of LH receptors is hormone-dependent (You et al, 2000; Johnson and Bridgham, 2001), if the expression of these regulatory hormones is dependent on photo-experience, then LH activity may also vary with photo-experience and potentially contribute to the age-related variation observed in early reproductive development.…”

Induction of Serum Amyloid A Genes Is Associated with Growth and Apoptosis of HC11 Mammary Epithelial Cells

“…The levels were analyzed and normalized as described previously (data not shown). 27,28) The slopes of the amplification curves of the RT-PCR products were constant from 24 to 30 cycles, and products were quantified every other cycle in six independent experiments. The amplified products were separated by electrophoresis on a 1.2% agarose gel, visualized with ethidium bromide, and analyzed by Multi-Analyst (Bio-Rad).…”

Sexual hearing: The influence of sex hormones on acoustic communication in frogs

“…LHR was traditionally thought to be expressed only in the gonads, in accord with the role of gonadotropins in stimulating the release of gonadal steroids. However, LHR has since been found in the neural tissues of birds, mammals and frogs (Lei et al, 1993; You et al, 2000; Rao et al, 2004; Yang et al, 2007). These data suggest that gonadotropins may act directly in the brain to regulate reproductive behaviors, in addition to inducing steroid hormone production (Lei and Rao, 2001).…”