Premium
CRM1 mediates nuclear export of HDAC7 independently of HDAC7 phosphorylation and association with 14‐3‐3s
Author(s) -
Gao Chengzhuo,
Li Xiaofang,
Lam Minh,
Liu Yu,
Chakraborty Sharmistha,
Kao Hung-Ying
Publication year - 2006
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/j.febslet.2006.08.038
Subject(s) - phosphorylation , nuclear export signal , cytoplasm , nuclear transport , microbiology and biotechnology , nucleus , mutant , cell nucleus , biology , chemistry , biochemistry , gene
CRM1, 14‐3‐3 proteins, and CaMK play important roles in trafficking of HDAC7, but the interplay between these proteins in this process is not clearly understood. Here, we show that CRM1 is capable of promoting cytoplasmic localization of wild‐type and mutant HDAC7 (S178A/S344A/S479A), which is normally found in the nucleus. Using phospho‐specific antibodies to HDAC7, we demonstrate that CaMK I promotes phosphorylation of S178, S344, and S479 of HDAC7. We also show that endogenous S178‐phosphorylated HDAC7 is localized in both the nucleus and the cytoplasm, whereas S344‐ and S479‐phosphorylated HDAC7 are exclusively localized in the nucleus. An HDAC7 mutant, S178E/S344E/S479E, which lost the ability to bind 14‐3‐3s, is localized in both the nucleus and the cytoplasm. Furthermore, the nuclear export of S178E/S344E/S479E is inhibited by LMB, but is enhanced by the CRM1. Taken together, these results strongly suggest that CRM1 mediated‐nuclear export of HDAC7 is independent of HDAC7 phosphorylation and its association with 14‐3‐3s.