Role of CD164 in Skeletal Myogenesis

CD164 在骨骼肌生成中的作用

基本信息

批准号：
7348397
负责人：
Robert S. Krauss
金额：
$ 31.19万
依托单位：
ICAHN SCHOOL OF MEDICINE AT MOUNT SINAI
依托单位国家：
美国
项目类别：
财政年份：
2004
资助国家：
美国
起止时间：
2004-02-18 至 2009-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7348397
关键词：
Adhesions Affinity BHLH Protein Biochemical Biological Blood C-terminal Carbohydrates Cell Differentiation process Cell Line Cell Proliferation Regulation Cell Surface Proteins Cell surface Cells Chimeric Proteins Class Cysteine Cytoplasmic Tail Data Effector Cell Endosomes Enzymes Epitopes Family Feedback Genes Genetic Transcription Hematopoietic Leukocyte Trafficking Leukocytes Ligands Light Link Lysosomes Mediating Methods Molecular Genetics Mucin-2 Staining Method Mucins Mus Muscle Muscle Development Mutagenesis Mutation Myf-6 myogenic factor Myoblasts Myogenin Neuraminidase O-sialoglycoprotein endopeptidase Pattern Peptide Signal Sequences Phenotype Plasmids Play Polysaccharides Process Proliferating Proline Protein Overexpression Proteins Protocols documentation Rate Reagent Regulation Reporting Research Role Selectins Serine Skeletal Muscle Skeletal system Structure Testing Threonine Tissues Yeasts base cDNA Library carbohydrate structure expression cloning in vivo inhibitor/antagonist myocyte-specific enhancer-binding factor 2 myogenesis receptor research study sialomucin sialomucins transcription factor

项目摘要

DESCRIPTION (provided by applicant): Determination and differentiation of the skeletal muscle lineage is controlled by the MyoD family of myogenic transcription factors. These factors, along with the MEF-2 family of transcription factors, auto-activate and cross-activate the expression of each other, resulting in an autoregulatory, positive feedback network that maintains the myogenic phenotype. Determination and differentiation of cells in this lineage also require cell-cell contact between muscle precursors. However, the identities of the cell surface proteins involved in this phenomenon, and their specific roles in myogenesis, are not well understood. Sialomucins are cell surface proteins characterized by mucin domains, which are proline-, serine-, and threonine-rich regions on which a high percentage of the serine and threonine residues are O-glycosylated. These O-linked glycans are central to sialomucin function, as specific sialomucins are known to serve as high affinity ligands for selectins; selectins are transmembrane receptors that recognize sialylated carbohydrate structures on these sialomucins during leukocyte trafficking. The biological roles of sialomucins outside of leukocyte trafficking are poorly understood. We have identified Cd164 as a gene expressed in proliferating C2C12 myoblasts that is specifically upregulated during differentiation. Cd164 encodes a widely expressed cell surface sialomucin that has been implicated in regulation of cell proliferation, differentiation and adhesion of hematopoietic precursors. Stable overexpression of Cd164 enhances myoblast differentiation. Treatment of C2C12 cells with sialidase or O-sialoglycoprotease, two enzymes which destroy functional epitopes on CD164, also inhibits differentiation. Taken together, we hypothesize that CD164 is a likely effector of the need of cell-cell contact in myogenesis and that carbohydrate-based cell recognition may be involved in this process. The Specific Aims are: 1) to identify structural determinants of the pro-myogenic activity of CD164; 2) to identify counter-receptors for CD164; and 3) to investigate the role of CD164 in myogenesis in vivo. These experiments will provide information critical to molecular and genetic understanding of CD164's role in myogenesis. This research should therefore shed light on fundamental processes by which skeletal muscles develop.

描述（由申请人提供）：骨骼肌谱系的确定和分化是由肌源转录因子的 MyoD 家族控制的。这些因子与 MEF-2 转录因子家族一起自动激活和交叉激活彼此的表达，从而形成维持肌源表型的自动调节、正反馈网络。该谱系中细胞的确定和分化也需要肌肉前体之间的细胞与细胞接触。然而，参与这种现象的细胞表面蛋白的身份及其在肌生成中的具体作用尚不清楚。唾液粘蛋白是一种以粘蛋白结构域为特征的细胞表面蛋白，粘蛋白结构域是富含脯氨酸、丝氨酸和苏氨酸的区域，其上高比例的丝氨酸和苏氨酸残基被O-糖基化。这些 O 连接聚糖是唾液酸粘蛋白功能的核心，因为已知特定的唾液酸粘蛋白可作为选择素的高亲和力配体；选择素是跨膜受体，在白细胞运输过程中识别这些唾液酸粘蛋白上的唾液酸化碳水化合物结构。人们对唾液酸粘蛋白在白细胞运输之外的生物学作用知之甚少。我们已经确定 Cd164 是在增殖的 C2C12 成肌细胞中表达的基因，该基因在分化过程中特异性上调。 Cd164 编码一种广泛表达的细胞表面唾液粘蛋白，该蛋白参与细胞增殖、分化和造血前体细胞粘附的调节。 Cd164 的稳定过表达可增强成肌细胞分化。用唾液酸酶或 O-唾液酸糖蛋白酶（这两种酶可破坏 CD164 上的功能性表位）处理 C2C12 细胞也会抑制分化。综上所述，我们假设 CD164 可能是肌生成中细胞与细胞接触需求的效应器，并且基于碳水化合物的细胞识别可能参与该过程。具体目标是： 1) 确定 CD164 促肌原活性的结构决定因素； 2) 鉴定CD164的反受体； 3）研究CD164在体内肌生成中的作用。这些实验将为理解 CD164 在肌生成中的作用提供重要的分子和遗传学信息。因此，这项研究应该揭示骨骼肌发育的基本过程。