The QKI-6 RNA binding protein localizes with the MBP mRNAs in stress granules of glial cells.
BACKGROUND
The quaking viable (qk(v)) mouse has several developmental defects that result in rapid tremors in the hind limbs. The qkI gene expresses three major alternatively spliced mRNAs (5, 6 and 7 kb) that encode the QKI-5, QKI-6 and QKI-7 RNA binding proteins that differ in their C-terminal 30 amino acids. The QKI isoforms are known to regulate RNA metabolism within oligodendrocytes, however, little is known about their roles during cellular stress.


RESULTS
In this study, we report an interaction between the QKI-6 isoform and a component of the RNA induced silencing complex (RISC), argonaute 2 (Ago2). We show in glial cells that QKI-6 co-localizes with Ago2 and the myelin basic protein mRNA in cytoplasmic stress granules.


CONCLUSIONS
Our findings define the QKI isoforms as Ago2-interacting proteins. We also identify the QKI-6 isoform as a new component of stress granules in glial cells.
Wang
Yunling
Y
Terry Fox Molecular Oncology Group, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, Bloomfield Center for Research on Aging, McGill University, Montréal, Québec, Canada.
Lacroix
Geneviève
G
Haines
Jeffery
J
Doukhanine
Evgueni
E
Almazan
Guillermina
G
Richard
Stéphane
S
D000818:Animals; D060565:Argonaute Proteins; D002460:Cell Line; D003594:Cytoplasmic Granules / Q000378:metabolism*; D015852:Eukaryotic Initiation Factor-2 / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D004676:Myelin Basic Protein; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D009457:Neuroglia / Q000378:metabolism*; D018384:Oxidative Stress; D011485:Protein Binding; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
C526735:Ago2 protein, mouse; D060565:Argonaute Proteins; D015852:Eukaryotic Initiation Factor-2; C499047:Mbp protein, mouse; D004676:Myelin Basic Protein; D009419:Nerve Tissue Proteins; D020033:Protein Isoforms; C098217:Qk protein, mouse; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D014157:Transcription Factors