High impact information on KCNJ16

• Kir5.1 coexpressed with PSD-95 located on the plasma membrane in a clustered manner, while the Kir5.1 subunit expressed alone distributed mostly in cytoplasm, probably due to rapid internalization [1].
• The binding of Kir5.1 with PSD-95 was prevented by protein kinase A (PKA)-mediated phosphorylation of its carboxyl terminus [1].
• Identification of a heteromeric interaction that influences the rectification, gating, and pH sensitivity of Kir4.1/Kir5.1 potassium channels [2].
• 1/Kir5.1 channel may therefore sense intracellular pH in renal epithelium and be involved in the regulation of acid-base homeostasis [3].
• 4. Oocytes co-injected with cRNA for mKir4.2 and Kir5.1, a protein that does not form functional homomeric channels, displayed membrane currents with properties distinct from those expressing mKir4.2 alone [4].

Biological context of KCNJ16

• This human KCNJ16 was mapped to chromosome 17q25 [5].
• Tissue distribution studies showed that human KCNJ16 is significantly expressed in human kidney, pancreas and thyroid gland [5].
• By comparing all Kirs using the motifs, we found the same amino acid sequence in Kir5.1, and demonstrated the pH sensitivity in heteromeric Kir4.1 and Kir5.1 channels to be pK approximately 7 [6].

Anatomical context of KCNJ16

• In the brain, Kir5.1 mRNA is restricted to the evolutionary older parts of the hindbrain, midbrain and diencephalon and overlaps with Kir2.1 in the superior/inferior colliculus and the pontine region [7].

Other interactions of KCNJ16

• The hKir5.1 gene KCNJ16 is assigned to chromosomal region 17q23.1-24.2, and is separated by only 34 kb from the hKir2.1 gene (KCNJ2) [7].
• Co-injected oocytes displayed larger currents than mKir4.2, with novel kinetic properties and an increased sensitivity to Ba2+ block at negative potentials, suggesting that mKir4.2 forms functional heteromultimeric channels with Kir5.1, as has been shown for Kir4.1 5 [4].

Analytical, diagnostic and therapeutic context of KCNJ16

• Western blot analysis using specific antibodies revealed that Kir4.1 and Kir5.1 proteins were expressed in kidney and brain, but co-immunoprecipitated only from kidney [3].

References