Coordinated expression of splice variants for luteinizing hormone receptor messenger RNA during the development of bovine corpora lutea

摘要

Using primers designed to amplify the coding region of the cattle LH receptor, 4 distinct bands were observed in corpora lutea, theca cells and granulosa cells by reverse transcription-polymerase chain reaction (RT-PCR). Sequencing of the RT-PCR products revealed that the largest form (519 bp) was the full-length A form of the LH receptor and that the 3 shorter forms (438, 253 and 172 bp) were its splicing variants. Splicing patterns of the 438-, 253- and 172-bp forms were identical to the F, B andG forms respectively found in the sheep ovary. Semiquantitative RT-PCR showed that the relative intensities of all 4 forms of LH receptor mRNA increased (P<0.05) from stage I (days 1-4; day 1 = day of ovulation) to stage IIS (days 5-10, corpus luteum (CL) weight <4 g), and from stage IIS to IIL (days 5-10, CL weight >=4 g). The intensities of all forms of LH receptor mRNA decreased slightly, but not significantly, from stage IIL to III (days 11-17). The ratios of the levels of all forms did not change significantly during development of the corpus luteum. Determination of the steady-state levels of LH receptor mRNA by northern blotting during the development of the CL showed changes similar to those seen with semiquantitative RT-PCR.