RESUMO
Eukaryotic gene expression is known as a multistep process of high complexity. Transcription is one of cardinal and tightly regulated phase during gene expression. To provide accurate and precise work of gene regulation apparatus including a plethora of modification of chromatin structure and nucleosome dynamic turnover must be occurred. All transcription steps are under control of large multiprotein coactivator complexes. In this review we discuss an evolutionary conservative SAGA complex, which acetylates and deubiquitinates histones during transcription activation and furthermore is involved in subsequent stages of mRNP biogenesis and export.
Assuntos
Regulação da Expressão Gênica , Complexos Multiproteicos/genética , Proteínas de Saccharomyces cerevisiae/genética , Transativadores/genética , Transcrição Gênica , Acetilação , Histonas/genética , Histonas/metabolismo , Complexos Multiproteicos/metabolismo , Ribonucleoproteínas/genética , Ribonucleoproteínas/imunologia , Saccharomyces cerevisiae/genética , UbiquitinaçãoRESUMO
SAGA is a histone acetyltransferase complex, that cotranscriptionally performs histone modifications and is implicated in regulation of gene expression at the level of changes in chromatin structure. SAGA is also involved in mRNP biogenesis and export. In this review, we examined a contribution of SAGA and its subunits in the development. We also discuss the diseases associated with impaired activity of SAGA subunits.
Assuntos
Proteínas de Drosophila/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Histona Acetiltransferases/biossíntese , Proteínas de Saccharomyces cerevisiae/genética , Transativadores/genética , Transcrição Gênica , Acetilação , Animais , Proteínas de Drosophila/genética , Drosophila melanogaster , Histona Acetiltransferases/genética , Histonas/genética , Histonas/metabolismo , Regiões Promotoras Genéticas , Ribonucleoproteínas/genética , Ribonucleoproteínas/imunologia , Saccharomyces cerevisiae/genética , Ubiquitinação/genéticaRESUMO
The results of systemic investigations devoted to the role of the proteins SAYP and ENY2 from Drosophila melanogaster in the regulation of different stages of gene expression are presented. The gene expression is a system of multistage processes involving the preparation of the chromatin matrix, initiation of transcription, mRNA synthesis, as well as the formation of mPNR particles, their export, and translation in the cytoplasm. At each of these stages, a great number of factors present6ed usually by protein complexes consisting of different subunits work. An analysis of the available evidence indicated that the transcription coactivators SAYP and ENY2 act in gene expression as cooperative nanoregulators, thereby determining the molecular mechanisms of coordination of spatial and temporal characteristics of the processes involved in the realization of genetic information.
Assuntos
Proteínas de Drosophila , Complexos Multiproteicos , Fatores de Transcrição , Animais , Montagem e Desmontagem da Cromatina/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Transporte de RNA/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
The ENY2/Sus1 is a multifunctional transcription factor which couples transcription with mRNA export. It is the component of the SAGA/TFTC and TREX-2/AMEX protein complexes. Recently, we described the interaction of ENY2 with one more protein complex, THO. Moreover, our data indicate that ENY2 associates with other nuclear and cytoplasmic factors. Thus, being the component of a number of protein complexes, ENY2 plays the role of an adaptor molecule, involved into the integration of different cellular processes, specifically, subsequent stages of gene expression.
