Depletion of hCINAP by RNA interference causes defects in Cajal body formation, histone transcription, and cell viability.
hCINAP is a highly conserved and ubiquitously expressed protein in eukaryotic organisms and its overexpression decreases the average number of Cajal bodies (CBs) with diverse nuclear functions. Here, we report that hCINAP is associated with important components of CBs. Depletion of hCINAP by RNA interference causes defects in CB formation and disrupts subcellular localizations of its components including coilin, survival motor neurons protein, spliceosomal small nuclear ribonucleoproteins, and nuclear protein ataxia-telangiectasia. Moreover, knockdown of hCINAP expression results in marked reduction of histone transcription, lower levels of U small nuclear RNAs (U1, U2, U4, and U5), and a loss of cell viability. Detection of increased caspase-3 activities in hCINAP-depleted cells indicate that apoptosis is one of the reasons for the loss of viability. Altogether, these data suggest that hCINAP is essential for the formation of canonical CBs, histone transcription, and cell viability.
Zhang
Jinfang
J
National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing, 100871, China.
Zhang
Feiyun
F
Zheng
Xiaofeng
X
D001483:Base Sequence; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D020541:Coiled Bodies / Q000378:metabolism*; D017931:DNA Primers / Q000235:genetics; D004268:DNA-Binding Proteins; D006367:HeLa Cells; D006657:Histones / Q000235:genetics*; D006801:Humans; D066298:In Vitro Techniques; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D012342:RNA, Small Nuclear / Q000378:metabolism; D055532:SMN Complex Proteins / Q000378:metabolism; D014158:Transcription, Genetic
D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D017931:DNA Primers; D004268:DNA-Binding Proteins; D006657:Histones; C101693:NPAT protein, human; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D012342:RNA, Small Nuclear; D055532:SMN Complex Proteins; C432963:TSPYL2 protein, human; C047458:fibrillarin; C068921:p80-coilin