Interaction between emerin and nuclear lamins.
Emerin is an inner nuclear membrane protein that is involved in X-linked recessive Emery-Dreifuss muscular dystrophy (X-EDMD). Although the function of this protein is still unknown, we revealed that C-terminus transmembrane domain-truncated emerin (amino acid 1-225) binds to lamin A with higher affinity than lamin C. Screening for the emerin binding protein and immunoprecipitation analysis showed that lamin A binds to emerin specifically. We also used the yeast two-hybrid system to clarify that this interaction requires the top half of the tail domain (amino acid 384-566) of lamin A. Lamin A and lamin C are alternative splicing products of the lamin A/C gene that is responsible for autosomal dominant Emery-Dreifuss muscular dystrophy (AD-EDMD). These results indicate that the emerin-lamin interaction requires the tail domains of lamin A and lamin C. The data also suggest that the lamin A-specific region (amino acids 567-664) plays some indirect role in the difference in emerin-binding capacity between lamin A and lamin C. This is the first report that refers the difference between lamin A and lamin C in the interaction with emerin. These data also suggest that lamin A is important for nuclear membrane integrity.
Sakaki
M
M
Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
Koike
H
H
Takahashi
N
N
Sasagawa
N
N
Tomioka
S
S
Arahata
K
K
Ishiura
S
S
D000818:Animals; D066298:In Vitro Techniques; D034904:Lamin Type A; D034882:Lamins; D008099:Liver / Q000166:cytology / Q000378:metabolism; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009132:Muscles / Q000166:cytology / Q000378:metabolism; D009685:Nuclear Envelope / Q000737:chemistry / Q000502:physiology; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology; D051381:Rats; D020539:Sequence Analysis, Protein; D013946:Thymopoietins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020798:Two-Hybrid System Techniques / Q000706:statistics & numerical data
D034904:Lamin Type A; D034882:Lamins; D008565:Membrane Proteins; D009687:Nuclear Proteins; D013946:Thymopoietins; C092710:emerin; C440308:lamin C