Experimental study on the new significant function domains of KCHIP1 protein.
Human K(v) channel interacting protein 1 (KCHIP1) is a new member of the neural calcium binding protein superfamily. Theoretically KCHIP1 has several calcium binding domains and two myristoylation sites. In this study, we demonstrated that the calcium binding domains and myristoylation sites were functional. The first, through running SDS-PAGE gel, we testified its ability of binding Ca(2+) with obvious discrepancy of the electrophoresis migrating rate after binding Ca(2+). Then, through the techniques of fused green fluorescence protein and site-directed mutagenesis, we demonstrated that wild type KCHIP1 protein accumulated in the secretory vesicles of Golgi body. In contrast, its two mutated forms without myristoylation sites accumulated throughout the whole cytoplasm. These observations indicate that KCHIP1 protein has a myristoylation motif mediating the interaction between KCHIP1 protein and membrane.
Liu
Zheng
Z
Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300192, China. liuzheng19752002@yahoo.com.cn
Xiao
Xiang-Jun
XJ
Fan
Fei-Yue
FY
Sun
Yuan-Ming
YM
Li
Yu-Min
YM
Yang
Fu-Jun
FJ
D000818:Animals; D019556:COS Cells; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002522:Chlorocebus aethiops; D006801:Humans; D051605:Kv Channel-Interacting Proteins / Q000737:chemistry* / Q000502:physiology*; D015221:Potassium Channels / Q000378:metabolism*; D024642:Potassium Channels, Voltage-Gated / Q000378:metabolism; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014162:Transfection
D002135:Calcium-Binding Proteins; C496750:KCNIP1 protein, human; D051605:Kv Channel-Interacting Proteins; D015221:Potassium Channels; D024642:Potassium Channels, Voltage-Gated; D011993:Recombinant Fusion Proteins; D002118:Calcium