抗體，也叫免疫球蛋白（Ig），是一種能特異性結合抗原的糖蛋白，而抗原是在易感染動物體內引發抗體產生的物質。在體內，抗體是由于外源性分子的侵襲而產生的。抗體以一個或者多個Y字形單體存在，每個Y字形單體由4條多肽鏈組成，包含兩條相同的重鏈和兩條相同的輕鏈。輕鏈和重鏈是根據它們的分子量大小來命名的。Y字形結構的頂端是可變區，為抗原結合部位。任何一個抗體的輕鏈都可以分為κ或λ型（基于小分子多肽結構上的差異），每一個抗體的重鏈則決定了它的類或型。
lamin A/C(LMNA) Homo sapiens The nuclear lamina consists of a two-dimensional matrix of proteins located next to the inner nuclear membrane. The lamin family of proteins make up the matrix and are highly conserved in evolution. During mitosis, the lamina matrix is reversibly disassembled as the lamin proteins are phosphorylated. Lamin proteins are thought to be involved in nuclear stability, chromatin structure and gene expression. Vertebrate lamins consist of two types, A and B. Alternative splicing results in multiple transcript variants. Mutations in this gene lead to several diseases: Emery-Dreifuss muscular dystrophy, familial partial lipodystrophy, limb girdle muscular dystrophy, dilated cardiomyopathy, Charcot-Marie-Tooth disease, and Hutchinson-Gilford progeria syndrome. [provided by RefSeq, Apr 2012]
備注：圖片僅供參考。僅供科研，不可用于臨床。
