目的:选择性聚腺苷酸化(APA)是一种共转录过程,可导致mRNA3'末端的同工型多样性。已知APA在分化过程中发生,在癌症和自身免疫性疾病等疾病中观察到其失调。以前已经报道3T3-L1细胞分化为脂肪细胞导致mRNAs的整体延长。但参与这一调控的蛋白质尚未被鉴定。裂解和聚腺苷酸化(C/P)复合物亚基的表达水平可以调节poly(A)位点的选择,这反过来又会影响不同的细胞活动。在本文中,我们研究了3T3-L1分化过程中C/P蛋白水平的变化。
结果:我们观察到,尽管这些蛋白质的RNA表达在分化过程中没有变化,某些亚基的蛋白质水平确实会发生变化,包括CPSF73水平的降低,CPSF73是在poly(A)位点切割的核酸酶。然而,单独的CPSF73过表达不影响分化的效率和速率。
OBJECTIVE: Alternative polyadenylation (APA) is a co-transcriptional process that leads to isoform diversity in the 3\' ends of mRNAs. APA is known to occur during differentiation, and its dysregulation is observed in diseases like cancer and autoimmune disorders. It has been previously reported that differentiation of 3T3-L1 cells to adipocytes leads to an overall lengthening of mRNAs, but the proteins involved in this regulation have not been identified. The expression levels of subunits of the cleavage and polyadenylation (C/P) complex can regulate the choice of poly(A) site, which in turn can affect different cellular activities. In this paper, we studied the change in levels of C/P proteins during 3T3-L1 differentiation.
RESULTS: We observed that while the RNA expression of these proteins is unchanged during differentiation, the protein levels of some subunits do change, including a decrease in levels of CPSF73, the nuclease that cuts at the poly(A) site. However, overexpression of CPSF73 alone does not affect the efficiency and rate of differentiation.