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PubMed · 9208842

Functionally distinct isoforms of STAT5 are generated by protein processing.

M Azam·C Lee·I Strehlow·C Schindler
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Abstract

The interleukin-3 family of cytokines, which play an important role in the development of myeloid lineages, transduce signals through the JAK-STAT pathway. Previous studies demonstrate that this process entails the activation of four distinct isoforms of STAT5, where two shorter isoforms are activated in a distinct population of cells. We now demonstrate that the shorter isoforms represent carboxy-terminal truncations. Moreover, these truncations are not generated by RNA processing, but by a specific proteolytic activity. Consistent with the notion that truncated STAT5 isoforms transduce distinct signals, they fail to promote the activation of several known interleukin-3 target genes. These studies suggest that the activity of a specific protease may play a critical role in defining the biological responses transduced by STAT5.

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Cells, CulturedDNA-Binding ProteinsGene Expression RegulationHumansInterleukin-3Milk ProteinsMolecular WeightProtein Processing, Post-TranslationalRNA Processing, Post-TranscriptionalRNA, MessengerSTAT5 Transcription FactorSignal TransductionStructure-Activity RelationshipTrans-ActivatorsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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M Azam, C Lee, I Strehlow, C Schindler. 1997. Functionally distinct isoforms of STAT5 are generated by protein processing.. https://doi.org/10.1016/s1074-7613(00)80445-8

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