Comparative analysis of cone and rod transducins using chimeric G? subunits.
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ABSTRACT:
SUBMITTER: Gopalakrishna KN
PROVIDER: S-EPMC3291952 | biostudies-literature | 2012 Feb
REPOSITORIES: biostudies-literature
Publications
Comparative analysis of cone and rod transducins using chimeric Gα subunits.
Gopalakrishna Kota N KN Boyd Kimberly K KK Artemyev Nikolai O NO
Biochemistry 20120216 8
The molecular nature of transducin-α subunits (Gα(t)) may contribute to the distinct physiology of cone and rod photoreceptors. Biochemical properties of mammalian cone Gα(t2) subunits and their differences with rod Gα(t1) are largely unknown. Here, we examined properties of chimeric Gα(t2) in comparison with its rod counterpart. The key biochemical difference between the rod- and cone-like Gα(t) was ~10-fold higher intrinsic nucleotide exchange on the chimeric Gα(t2). Presented mutational analy ...[more]
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