Identification of the High Molecular Weight Isoform of Phostensin

International Journal of Molecular Sciences

Yu-Shan Lin³  Hsien-Lu Huang¹  Wei-Ting Liu³  Ta-Hsien Lin² 

[1] Department of Nutrition and Health Science, Fooyin University, Kaohsiung 83102, Taiwan; E-Mail:;Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei 11221, Taiwan;Department of Life Science and Institute of Molecular Biology, National Chung Cheng University, Chia-Yi 62102, Taiwan; E-Mails:

关键词: phostensin-α;    phostensin-β;    KIAA1949;    protein phosphatase-1;    actin-binding protein;   

DOI  :  10.3390/ijms15011068

来源: mdpi

【 摘 要 】

Phostensin is encoded by KIAA1949. 5′-RACEanalysis has been used to identify the translation start site of phostensin mRNA, indicating that it encodes 165 amino acids with an apparent molecular weight of 26 kDa on SDS-PAGE. This low-molecular-weight phostensin is present in human peripheral blood mononuclear cells and many leukemic cell lines. Phostensin is a protein phosphatase-1(PP1) binding protein. It also contains one actin-binding motif at its C-terminal region and binds to the pointed ends of actin filaments, modulating actin dynamics. In the current study, a high-molecular-weight phostensin is identified by using immunoprecipitationin combination with a proteomic approach. This new species of phostensin is also encoded by KIAA1949 and consists of 613 amino acids with an apparent molecular weight of 110 kDa on SDS-PAGE. The low-molecular-weight and high-molecular-weight phostensins were named as phostensin-α and phostensin-β, respectively. Although phostensin-α is the C-terminal region of phostensin-β, it is not degraded from phostensin-β. Phostensin-β is capable of associating with PP1 and actin filaments, and is present in many cell lines.

【 授权许可】

CC BY   
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