Jeeyeon Cha, Xin Tong, Katie C Coate, Min Guo, Jin-Hua Liu, Garrett Reynolds, Emily M Walker, Richard A Stein, Hassane Mchaourab, Roland Stein
{"title":"确定控制胰岛素基因活性的 MAFA 和 MAFB 转录因子的独特结构特征。","authors":"Jeeyeon Cha, Xin Tong, Katie C Coate, Min Guo, Jin-Hua Liu, Garrett Reynolds, Emily M Walker, Richard A Stein, Hassane Mchaourab, Roland Stein","doi":"10.1016/j.jbc.2024.107938","DOIUrl":null,"url":null,"abstract":"<p><p>MAFA and MAFB are related basic-leucine-zipper domain-containing transcription factors which have important overlapping and distinct regulatory roles in a variety of cellular contexts, including hormone production in pancreatic islet cells. Here we first examined how mutating conserved MAF protein-DNA contact sites obtained from X-ray crystal structure analysis impacted their DNA-binding and Insulin enhancer-driven activity. While most of these interactions were essential and their disruption severely compromised activity, we identified that regions outside of these contact sites also contributed to transcriptional activity. AlphaFold 2, an artificial intelligence-based structural prediction program, was used to determine if there were also differences in the three-dimensional organization of the non-DNA binding/dimerization sequences of MAFA and MAFB. This analysis was conducted on the wildtype (WT) proteins as well as the pathogenic MAFA<sup>Ser64Phe</sup> and MAFB<sup>Ser70Ala</sup>trans-activation domain mutants, with differences revealed between MAFA<sup>WT</sup> and MAFB<sup>WT</sup> as well as between MAFA<sup>Ser64Phe</sup> and MAFA<sup>WT</sup>, but not between MAFB<sup>Ser70Ala</sup> and MAFB<sup>WT</sup>. Moreover, dissimilarities between these proteins were also observed in their ability to cooperatively stimulate Insulin enhancer-driven activity in the presence of other islet-enriched transcription factors. Analysis of MAFA and MAFB chimeras disclosed that these properties were influenced by their unique C-terminal region structural differences predicted by AlphaFold 2. Our findings have revealed key structural features of these closely related proteins that impact their ability to regulate gene expression.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0000,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Defining unique structural features in the MAFA and MAFB transcription factors that control Insulin gene activity.\",\"authors\":\"Jeeyeon Cha, Xin Tong, Katie C Coate, Min Guo, Jin-Hua Liu, Garrett Reynolds, Emily M Walker, Richard A Stein, Hassane Mchaourab, Roland Stein\",\"doi\":\"10.1016/j.jbc.2024.107938\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>MAFA and MAFB are related basic-leucine-zipper domain-containing transcription factors which have important overlapping and distinct regulatory roles in a variety of cellular contexts, including hormone production in pancreatic islet cells. Here we first examined how mutating conserved MAF protein-DNA contact sites obtained from X-ray crystal structure analysis impacted their DNA-binding and Insulin enhancer-driven activity. While most of these interactions were essential and their disruption severely compromised activity, we identified that regions outside of these contact sites also contributed to transcriptional activity. AlphaFold 2, an artificial intelligence-based structural prediction program, was used to determine if there were also differences in the three-dimensional organization of the non-DNA binding/dimerization sequences of MAFA and MAFB. This analysis was conducted on the wildtype (WT) proteins as well as the pathogenic MAFA<sup>Ser64Phe</sup> and MAFB<sup>Ser70Ala</sup>trans-activation domain mutants, with differences revealed between MAFA<sup>WT</sup> and MAFB<sup>WT</sup> as well as between MAFA<sup>Ser64Phe</sup> and MAFA<sup>WT</sup>, but not between MAFB<sup>Ser70Ala</sup> and MAFB<sup>WT</sup>. Moreover, dissimilarities between these proteins were also observed in their ability to cooperatively stimulate Insulin enhancer-driven activity in the presence of other islet-enriched transcription factors. Analysis of MAFA and MAFB chimeras disclosed that these properties were influenced by their unique C-terminal region structural differences predicted by AlphaFold 2. Our findings have revealed key structural features of these closely related proteins that impact their ability to regulate gene expression.</p>\",\"PeriodicalId\":15140,\"journal\":{\"name\":\"Journal of Biological Chemistry\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.0000,\"publicationDate\":\"2024-10-28\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Biological Chemistry\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.1016/j.jbc.2024.107938\",\"RegionNum\":2,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Biological Chemistry","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1016/j.jbc.2024.107938","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Defining unique structural features in the MAFA and MAFB transcription factors that control Insulin gene activity.
MAFA and MAFB are related basic-leucine-zipper domain-containing transcription factors which have important overlapping and distinct regulatory roles in a variety of cellular contexts, including hormone production in pancreatic islet cells. Here we first examined how mutating conserved MAF protein-DNA contact sites obtained from X-ray crystal structure analysis impacted their DNA-binding and Insulin enhancer-driven activity. While most of these interactions were essential and their disruption severely compromised activity, we identified that regions outside of these contact sites also contributed to transcriptional activity. AlphaFold 2, an artificial intelligence-based structural prediction program, was used to determine if there were also differences in the three-dimensional organization of the non-DNA binding/dimerization sequences of MAFA and MAFB. This analysis was conducted on the wildtype (WT) proteins as well as the pathogenic MAFASer64Phe and MAFBSer70Alatrans-activation domain mutants, with differences revealed between MAFAWT and MAFBWT as well as between MAFASer64Phe and MAFAWT, but not between MAFBSer70Ala and MAFBWT. Moreover, dissimilarities between these proteins were also observed in their ability to cooperatively stimulate Insulin enhancer-driven activity in the presence of other islet-enriched transcription factors. Analysis of MAFA and MAFB chimeras disclosed that these properties were influenced by their unique C-terminal region structural differences predicted by AlphaFold 2. Our findings have revealed key structural features of these closely related proteins that impact their ability to regulate gene expression.
期刊介绍:
The Journal of Biological Chemistry welcomes high-quality science that seeks to elucidate the molecular and cellular basis of biological processes. Papers published in JBC can therefore fall under the umbrellas of not only biological chemistry, chemical biology, or biochemistry, but also allied disciplines such as biophysics, systems biology, RNA biology, immunology, microbiology, neurobiology, epigenetics, computational biology, ’omics, and many more. The outcome of our focus on papers that contribute novel and important mechanistic insights, rather than on a particular topic area, is that JBC is truly a melting pot for scientists across disciplines. In addition, JBC welcomes papers that describe methods that will help scientists push their biochemical inquiries forward and resources that will be of use to the research community.