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Biology subjects

Tabaglio, T.

Publications and source records attributed to Tabaglio, T..

2 recordsLinked to original sources

Differential splice isoforms of mouse CDK2 play functionally redundant roles during mitotic and meiotic division

In most mammals, the cell cycle kinase; cyclin-dependent kinase 2 (CDK2) is expressed as two major isoforms due to the inclusion or exclusion of an alternatively spliced exon. The shorter CDK2 isoform: CDK2S, is expressed constitutively during the cell cycle and can be detected in many different tissue types. In contrast, the longer isoform: CDK2L, shows preferential expression in meiotically dividing cells of the germ cells and upon S-phase entry during mitotic cell division. Both CDK2L and CDK2S form heteromeric complexes with cyclins A2 and E1 in vitro. However, complexes comprised of each isoform differ considerably in their kinase activity towards known CDK substrates. It is currently unknown whether the long and short isoforms of CDK2 play functionally different roles in vivo during either mitotic and meiotic divisions as conventional knockout methodology leads to the loss of both isoforms. In this study, we find that both CDK2L and CDK2S are sufficient to support both mitotic and meiotic division when expressed in the absence of the other. This data contributes to the explanation of the apparent tolerance of the evolutionary loss of CDK2L expression in humans.

cell biology↗

HNRNPM controls circRNA biogenesis and splicing fidelity to sustain prostate cancer cell fitness

Cancer cells are differentially dependent on the splicing machinery compared to normal untransformed cells. The splicing machinery thus represents a potential therapeutic target in cancer. To identify splicing factors important for prostate cancer cell (PCa) cell growth, we performed a parallel pooled shRNA screen on in vitro passaged cells and in vivo xenografted PCa tumor lines. Our screen revealed HNRNPM as a potential regulator of PCa cell growth. RNA- and eCLIP-sequencing data suggest that HNRNPM is bound to transcripts of key homeostatic genes and that loss of HNRNPM binding in a subset of these genes results in aberrant exon inclusion and exon back-splicing events in target transcripts. In both linear and circular mis-spliced transcripts, HNRNPM appears to preferentially bind to GU-rich elements in long flanking proximal introns. Mimicry of HNRNPM dependent linear splicing events using splice-switching antisense oligonucleotides (SSOs) was sufficient to inhibit cell growth in HNRNPM expressing cells. This suggests that prostate cancer cell dependence on HNRNPM is likely a result of mis-splicing of key homeostatic coding and non-coding genes. Taken together, our data reveal a role for HNRNPM in supporting prostate cancer cell fitness, and also as a potential therapeutic target in PCa.

genomics↗