Fos 基因家族由 4 个成员组成：FOS、FOSB、FOSL1 和 FOSL2。这些基因编码的亮氨酸拉链蛋白可以与 JUN 家族的蛋白二聚化，从而形成转录因子复合物 AP-1。因此，FOS 蛋白被认为是细胞增殖、分化和转化的调节剂。在某些情况下，FOS 基因的表达也与凋亡细胞死亡有关。[RefSeq 提供，2008 年 7 月]

The Fos gene family consists of 4 members: FOS, FOSB, FOSL1, and FOSL2. These genes encode leucine zipper proteins that can dimerize with proteins of the JUN family, thereby forming the transcription factor complex AP-1. As such, the FOS proteins have been implicated as regulators of cell proliferation, differentiation, and transformation. In some cases, expression of the FOS gene has also been associated with apoptotic cell death. [provided by RefSeq, Jul 2008]