Channel Subunits that Recruit Src

Science's STKE  23 Jan 2001:
Vol. 2001, Issue 66, pp. tw7
DOI: 10.1126/stke.2001.66.tw7

Voltage-gated potassium channels that contain the Kv1.5 subunit associate with Src-family kinases through a Src homology 3 (SH3) domain and proline-rich domain on the enzyme and Kv1.5, respectively. However, other Kv subunits do not have a proline-rich region, yet are modified by these enzymes. Nitabach et al. report that this occurs because Kv1.5 recruits Src-like kinases to the vicinity of these other subunits in the context of heteromultimeric channels. The authors show that when expressed in Xenopus oocytes, phosphorylation of these subunits by kinases that are associated with an adjacent Kv1.5 subunit results in the suppression of channel currents. Hence, channel subunits can act as adaptors that facilitate appropriate channel modifications by harnessing the relevant signaling molecules. The authors suggest that this mechanism could generate a multitude of channel sensitivities to a variety of signaling pathways.

M. N. Nitabach, D. A. Llamas, R. C. Araneda, J. L. Intile, I. J. Thompson, Y. I. Zhou, T. C. Holmes, A mechanism for combinatorial regulation of electrical activity: Potassium channel subunits capable of functioning as Src homology 3-dependent adaptors. Proc. Natl. Acad. Sci. U.S.A. 98, 705-710 (2001). [Abstract] [Full Text]