LAMA4基因编码层粘连蛋白α4链,属于层粘连蛋白(laminin)基因家族,该家族是细胞外基质的重要组成成分,参与细胞粘附、迁移、分化和组织发育等过程。层粘连蛋白家族成员通常由α、β、γ三条链组成三聚体,具有十字形结构,其中α链决定其功能特异性。LAMA4主要在血管基底膜、心脏、胎盘和神经组织中表达,其编码的α4链与β1、γ1链结合形成层粘连蛋白-8(laminin-8),或与β2、γ1链结合形成层粘连蛋白-9(laminin-9),这两种层粘连蛋白在血管生成、内皮细胞粘附和肿瘤转移中发挥关键作用。LAMA4通过整合素受体(如α6β1、αvβ3)介导信号传导,调控细胞行为。LAMA4突变可能导致基底膜结构异常,与遗传性肾病、心肌病和某些神经肌肉疾病相关。研究表明,LAMA4表达降低会削弱血管稳定性,增加血管通透性,影响组织修复;而过表达则可能促进肿瘤血管生成和转移。在心血管系统中,LAMA4下调与心肌纤维化和心力衰竭相关,而其过表达可改善心脏功能。此外,LAMA4与阿尔茨海默病、糖尿病肾病和多种癌症(如乳腺癌、肺癌)的进展密切相关。该基因还参与调控其他基因如MMPs(基质金属蛋白酶)和VEGF(血管内皮生长因子)的表达,影响细胞外基质重塑和血管生成。层粘连蛋白家族成员的共性是提供结构支持并参与细胞-基质相互作用,但各成员因组织分布和结合伙伴不同而功能各异。LAMA4的独特之处在于其既参与发育过程中的组织构建,又在病理条件下如肿瘤微环境调控中起双重作用。
Laminins, a family of extracellular matrix glycoproteins, are the major noncollagenous constituent of basement membranes. They have been implicated in a wide variety of biological processes including cell adhesion, differentiation, migration, signaling, neurite outgrowth and metastasis. Laminins are composed of 3 non identical chains: laminin alpha, beta and gamma (formerly A, B1, and B2, respectively) and they form a cruciform structure consisting of 3 short arms, each formed by a different chain, and a long arm composed of all 3 chains. Each laminin chain is a multidomain protein encoded by a distinct gene. Several isoforms of each chain have been described. Different alpha, beta and gamma chain isomers combine to give rise to different heterotrimeric laminin isoforms which are designated by Arabic numerals in the order of their discovery, i.e. alpha1beta1gamma1 heterotrimer is laminin 1. The biological functions of the different chains and trimer molecules are largely unknown, but some of the chains have been shown to differ with respect to their tissue distribution, presumably reflecting diverse functions in vivo. This gene encodes the alpha chain isoform laminin, alpha 4. The domain structure of alpha 4 is similar to that of alpha 3, both of which resemble truncated versions of alpha 1 and alpha 2, in that approximately 1,200 residues at the N-terminus (domains IV, V and VI) have been lost. Laminin, alpha 4 contains the C-terminal G domain which distinguishes all alpha chains from the beta and gamma chains. The RNA analysis from adult and fetal tissues revealed developmental regulation of expression, however, the exact function of laminin, alpha 4 is not known. Tissue-specific utilization of alternative polyA-signal has been described in literature. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Aug 2011]
层粘连蛋白,一个家庭的细胞外基质糖蛋白,是基底膜的主要非胶原成分。他们已牵涉在多种生物学过程,包括细胞粘着,分化,迁移,信令,神经突向外生长和转移。层粘连蛋白组成的3个非同一链:层粘连蛋白α,β和γ(前身为A,B1和B2,分别)和他们形成了一个十字形结构,其中包括3短臂,每个由不同的链形成,一个长臂组成所有的3链。每个层粘连蛋白链是由不同的基因编码的蛋白质的多域。每条链的几种同工型已被描述。不同的α,β和γ链异构体结合以引起其通过阿拉伯数字在其发现的顺序指定不同异源层粘连蛋白同种型,即alpha1beta1gamma1异源是层粘连蛋白1的不同链和三聚体分子的生物功能在很大程度上是未知,但一些链已显示对于不同其组织分布,推测反映出体内多种功能。该基因编码的α链同种型层粘连蛋白,α-4.阿尔法4的域结构类似于阿尔法3,这两者的相似的α1和α2的截短形式,在N末端有大约1200的残基(域IV,V和VI)已经丢失。层粘连蛋白,α-4包含区别于β和γ链的所有的α链的C端G域。从成人和胎儿组织中的RNA的分析表明表达的发育调控,然而,层粘连蛋白的确切功能,α-4是未知的。替代多聚A信号的组织特异性利用率在文献中已有描述。在多个转录剪接变异体结果不同编码的亚型。 [由RefSeq的,2011年8月提供]
LAMA4基因(以及对应的蛋白质)的细胞分布位置:
LAMA4基因的本体(GO)信息:
| 名称 |
|---|
| 4151 PI3K-Akt signaling pathway [PATH:hsa04151] |
| 4512 ECM-receptor interaction [PATH:hsa04512] |
| 4510 Focal adhesion [PATH:hsa04510] |
| 5200 Pathways in cancer [PATH:hsa05200] |
| 5222 Small cell lung cancer [PATH:hsa05222] |
| 5146 Amoebiasis [PATH:hsa05146] |
| 5145 Toxoplasmosis [PATH:hsa05145] |
| 5143 African trypanosomiasis [PATH:hsa05143] |
| 名称 |
|---|
| ECM proteoglycans |
| Extracellular matrix organization |
| Laminin interactions |
| Non-integrin membrane-ECM interactions |
| 疾病名称 | 关系值 | NofPmids | NofSnps | 来源 |
| CARDIOMYOPATHY, DILATED, 1JJ | 0.24 | 1 | 2 | CLINVAR_UNIPROT |
| Spontaneous abortion | 0.12 | 1 | 0 | CTD_human |
| Junctional Epidermolysis Bullosa | 0.003528744 | 13 | 0 | BeFree |
| Glioma | 0.00272435 | 1 | 0 | LHGDN |
| Brain Neoplasms | 0.00272435 | 1 | 0 | LHGDN |
| Myocardial Infarction | 0.002638474 | 1 | 1 | BeFree_GAD |
| Atherosclerosis | 0.002367032 | 1 | 0 | GAD |
| Neoplasm Metastasis | 0.000814326 | 3 | 0 | BeFree |
| Adenocarcinoma | 0.000271442 | 1 | 0 | BeFree |
| Colorectal Carcinoma | 0.000271442 | 1 | 0 | BeFree |
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