DNA-Bound peptides control the mRNA transcription through CDK7.
The degradation of intracytosolic proteins has been well described. However, the degradation pathway and physiological functions of the DNA-Bound peptides, which are free of degradation by peptidase of the post-ubiquitin-proteasome pathway, are still unclear. In this study, the DNA-Bound peptides were isolated from barley germ and two main fractions of about 25 different peptides were obtained. The DNA-Bound peptides were found to inhibit the proliferation of HeLa cells in a series of experiments. The DNA-Bound peptides also significantly inhibited in vitro and in vivo DNA transcription activity by regulating the expression and the corresponding functions of CDK7. Furthermore, signaling issues involving NFkappaB and ERK1/2 were observed. Such data suggests that DNA transcription could be inhibited by the DNA-Bound peptides via the CDK7 pathway. Thus we concluded that some of the post-proteasomal peptides were involved in the regulation of eukaryotic mRNA transcription.
Lv
Xiaowen
X
Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China.
Wang
Jing
J
Dong
Zhiyuan
Z
Lv
Feijie
F
Qin
Yuchang
Y
D001483:Base Sequence; D015153:Blotting, Western; D018844:Cyclin-Dependent Kinases / Q000502:physiology*; D003587:Cytomegalovirus / Q000235:genetics; D004247:DNA / Q000378:metabolism*; D017931:DNA Primers; D006367:HeLa Cells; D001467:Hordeum / Q000166:cytology / Q000196:embryology; D006801:Humans; D008856:Microscopy, Fluorescence; D010455:Peptides / Q000494:pharmacology*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000737:chemistry; D014158:Transcription, Genetic / Q000187:drug effects*; D000095043:Cyclin-Dependent Kinase-Activating Kinase
D017931:DNA Primers; D010455:Peptides; D012333:RNA, Messenger; D004247:DNA; D018844:Cyclin-Dependent Kinases; D000095043:Cyclin-Dependent Kinase-Activating Kinase