The DEAD-Box Protein CYT-19 Uses Arginine Residues in Its C-Tail To Tether RNA Substrates.

ABSTRACT: DEAD-box proteins are nonprocessive RNA helicases that play diverse roles in cellular processes. The Neurospora crassa DEAD-box protein CYT-19 promotes mitochondrial group I intron splicing and functions as a general RNA chaperone. CYT-19 includes a disordered, arginine-rich "C-tail" that binds RNA, positioning the helicase core to capture and unwind nearby RNA helices. Here we probed the C-tail further by varying the number and positions of arginines within it. We found that removing sets of as few as four of the 11 arginines reduced RNA unwinding activity (k_cat/K_M) to a degree equivalent to that seen upon removal of the C-tail, suggesting that a minimum or "threshold" number of arginines is required. In addition, a mutant with 16 arginines displayed RNA unwinding ac

SUBMITTER: Busa VF 

PROVIDER: S-EPMC5960805 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature