Novel unconventional myosins in B cell homeostasis

B 细胞稳态中的新型非常规肌球蛋白

• 批准号: 10733725
• 负责人: Neetu Gupta
• 金额: $ 52.93万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2028-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10733725
• 关键词: Affect; American; Antibodies; Antibody Formation; Antibody Response; Antigens; Autoantibodies; Autoimmune; Autoimmune Diseases; Autoimmunity; B cell differentiation; B-Cell Activation; B-Cell Antigen Receptor; B-Lymphocytes; Binding; Biochemical; Biological Assay; Body part; Cell Count; Cell Differentiation process; Cell Survival; Cell physiology; Cells; Data; Development; Event; Gene Expression; Gene Expression Profiling; Generations; Genetic; Genetic Transcription; Goals; Health; Homeostasis; Hypergammaglobulinemia; Immunity; Immunologics; Immunoprecipitation; In Vitro; Interleukin-6; Investigation; Life; Link; Lymphocyte Activation; Mature B-Lymphocyte; Mediating; Messenger RNA; Mitochondria; Molecular; Molecular Abnormality; Multiprotein Complexes; Mus; Myosin ATPase; Pain; Patients; Personal Satisfaction; Phenotype; Plasma Cells; Post-Transcriptional Regulation; Process; Production; Proliferating; Protein Family; Proteins; Publishing; Quality of life; RNA; Receptor Signaling; Regulation; Reporting; Research; Role; Scaffolding Protein; Self Tolerance; Signal Transduction; Site; Splenocyte; Splenomegaly; Surface; Syndrome; Testing; Tissue-Specific Gene Expression; Transcript; Transgenic Mice; anti-IgM; autoimmune pathogenesis; body system; experimental study; fluorescence imaging; gain of function; genetic regulatory protein; high resolution imaging; humoral immunity deficiency; innovation; insight; loss of function; mRNA Decay; mRNA Stability; mRNA Transcript Degradation; mutant; novel; overexpression; pathogenic autoantibodies; plasma cell differentiation; posttranscriptional; prevent; response; single-cell RNA sequencing; transcription factor; transcriptome; transcriptome sequencing; transcriptomics

ABSTRACT Incurable autoimmune diseases afflict millions of Americans, cause pain and persistent damage to multiple organ systems, and have a major impact on patient health, well-being and quality of life. Increased B cell numbers, greater B cell activation and differentiation into plasma cells, and autoantibody production often characterize autoimmunity, signifying that dysregulated B cell survival and differentiation are critical steps in autoimmune pathogenesis. Identification of proteins and molecular events that regulate B cell survival, activation and differentiation is therefore critical for better mechanistic understanding of autoimmune disease development. Myo18A is a scaffolding protein with a unique domain organization that enables assembly of multiprotein complexes in various subcellular compartments of non-immune cells. We reported that B cells express Myo18A, and that its conditional deletion in B cells (Myo18A BKO) leads to an increase in mature B cells and plasma cells, splenomegaly, hypergammaglobulinemia, and development of autoantibodies. Interestingly, this profile overlaps with autoimmune manifestations reported in transgenic mice overexpressing the B cell survival factor BAFF, and in mice with genetic deletion of proteins involved in mRNA decay. In preliminary data, we observed that Myo18A-deficient B cells display features of greater BAFF responsiveness, including increased mitochondrial size and gene expression, and stronger pro-survival Akt signaling, indicating that Myo18A negatively regulates B cell response to BAFF. Additionally, deletion of Myo18A in B cells increased the basal expression and reduced the decay of mRNA encoding Blimp-1, a key transcription factor in B cell differentiation. Further, Myo18A in B cells bound to Blimp1 mRNA and co-localized with subcellular mRNA degradation sites, indicating that Myo18A is involved in post-transcriptional regulation and expression of Blimp- 1. Our published and preliminary data suggest that Myo18A is an important and previously unrecognized determinant in B cell immunity. Our specific aims are to test the hypotheses that (1) Myo18A restricts BCR and BAFF-R signaling to control B cell homeostasis, (2) Myo18A inhibits mRNA stability to inform B cell gene expression, and (3) Myo18A limits B cell differentiation by controlling the B cell transcriptome. The proposed research is innovative because it will establish a novel role for the unconventional myosin family protein Myo18A in preventing uncontrolled B cell activation and differentiation. Specifically, our research will identify a novel functional connection between Myo18A and B cell survival and differentiation through regulation of B cell antigen and BAFF responsiveness and post-transcriptional mRNA stability. This research is expected to have significant impact because it will enable better mechanistic understanding of the molecular processes that prevent exaggerated antibody development.

摘要 无法治愈的自身免疫性疾病折磨着数百万美国人，导致疼痛和多个器官的持续性损害 并对患者的健康、福祉和生活质量产生重大影响。B细胞数量增加， 更大的B细胞活化和分化为浆细胞，以及自身抗体的产生通常是特征 自身免疫，意味着失调的B细胞生存和分化是自身免疫的关键步骤 发病机制。调控B细胞存活、激活和死亡的蛋白质和分子事件的鉴定 因此，鉴别对于更好地从机制上理解自身免疫性疾病至关重要。 发展。Myo18A是一种支架蛋白，具有独特的结构域组织，能够组装 在非免疫细胞的各种亚细胞中的多蛋白复合体。我们报告了B细胞 表达Myo18A，并在B细胞中有条件地删除其(Myo18A BKO)导致成熟B细胞的增加 细胞和浆细胞，脾肿大，高丙种球蛋白血症，和自身抗体的发展。 有趣的是，这一特征与报告的转基因小鼠过度表达的自身免疫表现相重叠。 B细胞存活因子BAFF，并在基因缺失的小鼠体内参与蛋白的衰变。在……里面 初步数据，我们观察到Myo18A缺陷的B细胞表现出更强的BAFF反应性， 包括线粒体大小和基因表达增加，以及更强的促生存Akt信号，表明 Myo18A负性调节B细胞对BAFF的应答。此外，B细胞中Myo18A的缺失增加 编码关键转录因子Blimp-1的mRNA在B细胞中的基础表达和衰退 差异化。此外，B细胞中的Myo18A与Blimp1mRNA结合并与亚细胞mRNA共定位 降解位点，表明Myo18A参与了Blimp-1的转录后调控和表达 1.我们已发表的和初步的数据表明，Myo18A是一种重要的、以前未被认识的 B细胞免疫中的决定因素。我们的具体目标是检验以下假设：(1)Myo18A限制bcr 和BAFF-R信号调节B细胞的动态平衡；(2)Myo18A抑制mRNA的稳定性以告知B细胞基因 Myo18A通过控制B细胞转录组来限制B细胞的分化。建议数 这项研究具有创新性，因为它将为非传统肌球蛋白家族蛋白Myo18A确立一个新的角色 在防止不受控制的B细胞激活和分化方面。具体地说，我们的研究将确定一部小说 B细胞抗原调控下Myo18A与B细胞存活和分化的功能联系 以及BAFF的反应性和转录后mRNA的稳定性。这项研究预计将有 重大影响，因为它将使人们能够更好地从机制上理解 防止过度的抗体产生。

项目成果

Host metabolome predicts the severity and onset of acute toxicities induced by CAR T-cell therapy.

• DOI: 10.1182/bloodadvances.2022007456
• 发表时间: 2023-09-12
• 期刊: BLOOD ADVANCES
• 影响因子: 7.5
• 作者: Jalota, Akansha;Hershberger, Courtney E.;Patel, Manishkumar S.;Mian, Agrima;Faruqi, Aiman;Khademi, Gholamreza;Rotroff, Daniel M.;Hill, Brian T.;Gupta, Neetu
• 通讯作者: Gupta, Neetu