Molecular Endocrinology Laboratory, Animal Biochemistry Division, National Dairy Research Institute, Karnal, Haryana, India.
Gene. 2012 Aug 10;504(2):245-52. doi: 10.1016/j.gene.2012.04.090. Epub 2012 May 16.
In the present study, we describe the isolation and characterization of the transcripts encoding peroxisome proliferator-activated receptor gamma (PPARγ1 and PPARγ2) in buffalo ovary. 5' RACE experiments and sequence analysis showed that these transcripts (PPARγ1a, PPARγ1b and PPARγ2) were transcribed by the different promoter usage and alternative splicing of terminal 5'-exon. The distribution of these isoforms of PPARγ transcripts in different tissues (ovary, mammary gland, spleen, liver, lung, adipose tissue) was investigated using quantitative real time analysis. Tissue- and transcript-specific expression analyses showed that a transcript, transcribed from distal promoter, not only expressed preferentially in ovary but contributes predominantly to PPAR gamma expression in ovary. Western blot analysis of both, in vivo and in vitro, experiments also supported that PPARγ1 predominantly expressed in ovary. In buffalo granulosa cells culture, the isolated transcripts were found to be up-regulated by both natural (CLA) and synthetic (Rosiglitazone) ligands and effect was reversed by PPARγ antagonist GW9662. In conclusion, the present study identified an ovary-specific novel transcript, transcribed by distal promoter, predominantly expressed in ovary which could have functional relevance in buffalo ovary.
在本研究中，我们描述了水牛卵巢中过氧化物酶体增殖物激活受体 γ（PPARγ1 和 PPARγ2）转录本的分离和特征。5'RACE 实验和序列分析表明，这些转录本（PPARγ1a、PPARγ1b 和 PPARγ2）通过不同的启动子使用和末端 5'-外显子的选择性剪接转录。使用定量实时分析研究了这些 PPARγ 转录本异构体在不同组织（卵巢、乳腺、脾、肝、肺、脂肪组织）中的分布。组织和转录本特异性表达分析表明，从远端启动子转录的一种转录本不仅在卵巢中优先表达，而且主要有助于卵巢中 PPARγ 的表达。体内和体外实验的 Western blot 分析也支持 PPARγ1 主要在卵巢中表达。在水牛颗粒细胞培养中，发现分离的转录本被天然（CLA）和合成（罗格列酮）配体上调，这种作用被 PPARγ 拮抗剂 GW9662 逆转。总之，本研究鉴定了一种卵巢特异性的新型转录本，由远端启动子转录，主要在卵巢中表达，这可能与水牛卵巢的功能相关。
