RXRB（Retinoid X Receptor Beta）属于核受体超家族中的类视黄醇X受体（RXR）亚家族，该家族还包括RXRA和RXRG。这些受体通过与配体（如9-顺式维甲酸）结合形成同源或异源二聚体（如与维生素D受体、甲状腺激素受体等结合），调控靶基因的转录。RXRB主要在代谢活跃的组织（如肝脏、肾脏、脂肪和免疫系统）中表达，参与脂质代谢、葡萄糖稳态、炎症反应和细胞分化等过程。其表达产物是一种配体依赖的转录因子，通过结合特定DNA序列（如激素反应元件，HRE）激活或抑制下游基因（如参与脂肪酸氧化的PPARα通路）。突变可能导致功能丧失或异常激活，例如某些错义突变会干扰二聚化或配体结合能力，与代谢综合征、糖尿病或癌症（如甲状腺癌）相关。RXRB过表达可能增强脂解和胰岛素敏感性，但过度激活可能引发细胞凋亡或自身免疫反应；而表达降低则可能促进脂肪堆积和炎症，加剧代谢紊乱。RXR家族共性包括：依赖配体调控、形成多样二聚体组合以扩大调控范围，并在发育和代谢中发挥核心作用。目前中文术语"类视黄醇X受体"（原英文Retinoid X Receptor）存在争议，部分学者建议直译为"视黄酸X受体"。

该基因编码核受体的类视黄醇X受体（RXR）家族，其参与介导的视黄酸（RA）的影响的成员。所编码的蛋白质的形式同二聚体与视黄酸，甲状腺激素和维生素D受体，它们各自的应答元件同时增加DNA结合和转录的功能。此基因在染色体上位于主要组织相容性复合体（MHC）II类区域内6.备选剪接转录变体编码的多个同种型已被用于这个基因观察到。 [由RefSeq的，2012年7月提供]

RXRB, or Retinoid X Receptor Beta, is a member of the nuclear receptor superfamily, specifically belonging to the Retinoid X Receptor (RXR) subfamily alongside RXRA and RXRG. As a ligand-dependent transcription factor, RXRB functions by binding to specific ligands, such as 9-cis-retinoic acid, to form either homodimers or heterodimers with other nuclear receptors, including the vitamin D receptor and thyroid hormone receptor. These receptor complexes bind to hormone response elements (HREs) within the regulatory regions of target genes, thereby modulating their transcriptional activity. This mechanism is central to the regulation of lipid metabolism, glucose homeostasis, inflammatory responses, and cellular differentiation, with RXRB playing a particularly significant role in the PPARα pathway governing fatty acid oxidation. The gene is predominantly expressed in metabolically active tissues, including the liver, kidneys, adipose tissue, and the immune system. Dysregulation of RXRB function, whether through loss-of-function or gain-of-function mutations that impair dimerization or ligand binding, is implicated in various pathological conditions, including metabolic syndrome, diabetes, and certain cancers such as thyroid carcinoma. While overexpression of RXRB can enhance lipolysis and improve insulin sensitivity, excessive activation may paradoxically trigger apoptosis or autoimmune reactions, whereas reduced expression is associated with adiposity, chronic inflammation, and exacerbated metabolic disorders. The RXR family's ability to form diverse dimeric combinations allows for a broad regulatory scope, underscoring its critical role in both developmental processes and metabolic homeostasis.

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