TY - JOUR

T1 - Interaction between importin 13 and myopodin suggests a nuclear import pathway for myopodin

AU - Liang, Jie

AU - Ke, Guifen

AU - You, Wenjun

AU - Peng, Zi

AU - Lan, Jie

AU - Kalesse, Markus

AU - Tartakoff, Alan M.

AU - Kaplan, Feige

AU - Tao, Tao

N1 - Funding Information: Acknowledgments This work was supported by grants (#3047085 and #90608007 from the National Natural Science Foundation of China; #C0510003 from the Natural Science Foundation of Fujian Province; #2005-383 from the Ministry of Education of China) and a startup fund (#XK0014) from Xiamen University to Tao Tao.

PY - 2008/1

Y1 - 2008/1

N2 - Importin 13 is a member of the importin β superfamily of nuclear transport proteins and is expressed in multiple tissues at high levels both in humans and rodents, including fetal lung, brain, and heart. In order to elucidate potential functions of imp13 in the heart, we have used rat imp13 as bait to screen a human heart cDNA library and identified an interaction with the C-terminal peptide of myopodin (a.a. 360-698), an actin-bundling protein, associated with tumor-suppressor activity that localizes to both the cytoplasm and the nucleus. We have used GST-pull down assays and co-immunoprecipitation experiments to demonstrate an interaction between imp13 and full-length myopodin and observed that RanGTP dissociates the myopodin-imp13 complex. In studies of cultured cells, we show that both imp13 siRNA and a C-terminal fragment of imp13 protein prevent nuclear localization of myopodin. We, therefore, conclude that imp13 functions in myopodin import and we suggest that the regulation of these events is critical for normal and abnormal cellular differentiation.

AB - Importin 13 is a member of the importin β superfamily of nuclear transport proteins and is expressed in multiple tissues at high levels both in humans and rodents, including fetal lung, brain, and heart. In order to elucidate potential functions of imp13 in the heart, we have used rat imp13 as bait to screen a human heart cDNA library and identified an interaction with the C-terminal peptide of myopodin (a.a. 360-698), an actin-bundling protein, associated with tumor-suppressor activity that localizes to both the cytoplasm and the nucleus. We have used GST-pull down assays and co-immunoprecipitation experiments to demonstrate an interaction between imp13 and full-length myopodin and observed that RanGTP dissociates the myopodin-imp13 complex. In studies of cultured cells, we show that both imp13 siRNA and a C-terminal fragment of imp13 protein prevent nuclear localization of myopodin. We, therefore, conclude that imp13 functions in myopodin import and we suggest that the regulation of these events is critical for normal and abnormal cellular differentiation.

KW - Importin 13

KW - Interaction

KW - Myopodin

KW - Nuclear import

UR - http://www.scopus.com/inward/record.url?scp=36949022695&partnerID=8YFLogxK

U2 - 10.1007/s11010-007-9588-1

DO - 10.1007/s11010-007-9588-1

M3 - Article

C2 - 17828378

AN - SCOPUS:36949022695

VL - 307

SP - 93

EP - 100

JO - Molecular and Cellular Biochemistry

JF - Molecular and Cellular Biochemistry

SN - 0300-8177

IS - 1-2

ER -