FASTK
FASTK (Fas-activated serine/threonine kinase) was identified as a kinase whose activity rises rapidly after Fas death-receptor engagement during lymphocyte apoptosis. It localizes predominantly to mitochondria, and later work showed that it binds mitochondrial RNA and participates in processing transcripts of the ND6 gene, connecting it to respiratory chain biogenesis as well as to cell-death signaling. FASTK is the founding member of the FASTKD family, whose other members share the mitochondrial RNA-binding architecture. Because its physiological protein substrates remain uncertain, recombinant FASTK is used mainly for kinase-activity assays, RNA-binding studies and apoptosis-pathway investigations rather than for defined substrate work.
