Domain compatibility in Ire1 kinase is critical for the unfolded protein response.
The unfolded protein response is a mechanism to cope with endoplasmic reticulum stress. In Saccharomyces cerevisiae, Ire1 senses the stress and mediates a signaling cascade to upregulate responsive genes through an unusual HAC1 mRNA splicing. The splicing requires interconnected activity (kinase and endoribonuclease (RNase)) of Ire1 to cleave HAC1 mRNA at the non-canonical splice sites before translation into Hac1 transcription factor. Analysis of the truncated kinase domain from Ire1 homologs revealed that this domain is highly conserved. Characterization by domain swapping indicated that a functional ATP/ADP binding domain is minimally required. However the overall domain compatibility is critical for eliciting its full RNase function.
Poothong
Juthakorn
J
The Institute of Molecular Biosciences, Mahidol University, Salaya, Nakhon Pathom, Thailand.
Sopha
Pattarawut
P
Kaufman
Randal J
RJ
Tirasophon
Witoon
W
D004721:Endoplasmic Reticulum / Q000235:genetics / Q000378:metabolism; D004722:Endoribonucleases / Q000235:genetics / Q000378:metabolism*; D010770:Phosphotransferases / Q000235:genetics / Q000378:metabolism; D012326:RNA Splicing; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012260:Ribonucleases / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D056811:Unfolded Protein Response; D015854:Up-Regulation
D012333:RNA, Messenger; D014157:Transcription Factors; D010770:Phosphotransferases; D004722:Endoribonucleases; D012260:Ribonucleases