[8B7 spectrin--a new member of spectrin family].
OBJECTIVE
To analyze the nature of the protein encoded by 8B7cDNA (1 835 bp) and to examine the localization of the protein in cells.


METHODS
The nature of the protein was analyzed using Blastn, Blastp, and TMpred. Expressions of 8B7 mRNA in tissues and cells were examined by Northern blotting. Recombinant expression vectors for localization test were constructed and transfected into COS-7 cells. Fluorescence emission in cells was examined upon a laser scan confocal microscope.


RESULTS
The protein encoded by 8B7cDNA was 363 amino acids long and contained spectrin repeats. It was completely homologous to the C-terminal 363 amino acids of Enaptin, Nasprin-1, Mynel, and Syne-1 proteins. It belonged to Spectrin super-family and was called 8B7 spectrin. Northern blotting revealed a 1.8 kb mRNA expression in human spleen and small intestine tissues. EGFP-8B7 fusion protein was observed to express on the nuclear membrane and in the cytoplasm in a reticular form in a localization assay on COS-7 cells. The position of fluorescence in COS-7 cells transfected with pEGFP-delta SR8B7 was similar to that in the cells transfected with pEGFP-8B7cDNA.


CONCLUSIONS
8 B7 spectrin is a novel member of spectrin super-family. It localizes to the nuclear membrane and the cytoplasm in a reticular form in COS-7 cells. The localization is determined by the C-terminal KASH domain in 8B7 spectrin molecule.
Liu
Rong
R
Department of Immunology, Institute of Basic Medical Sciences, CAMS and PUMC, Beijing 100005, China.
Tian
Yun
Y
Ju
Ji-yu
JY
Wang
Yi
Y
Zhou
Yi-qun
YQ
Liu
Yin
Y
Zhu
Li-ping
LP
D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D019556:COS Cells; D002522:Chlorocebus aethiops; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D013049:Spectrin / Q000096:biosynthesis* / Q000737:chemistry* / Q000235:genetics; D014162:Transfection
D018076:DNA, Complementary; D012333:RNA, Messenger; D013049:Spectrin