PAX7是PAX基因家族中的一员，属于配对盒（PAX）转录因子家族，该家族共有9个成员（PAX1-PAX9），其共同特点是含有一个高度保守的DNA结合结构域——配对盒结构域，能够调控靶基因的表达，在胚胎发育、细胞分化和组织稳态中发挥关键作用。PAX7主要在骨骼肌卫星细胞中高表达，是肌肉干细胞（卫星细胞）维持自我更新和未分化状态的核心调控因子，其表达产物通过激活下游靶基因（如Myf5）促进肌肉再生和修复。PAX7的功能特点包括维持干细胞库的稳定性、抑制过早分化，并在肌肉损伤后激活卫星细胞增殖。若PAX7发生功能丧失性突变，会导致卫星细胞数量减少或功能缺陷，引发先天性肌病或肌肉再生障碍；而染色体易位导致的PAX7过表达与儿童横纹肌肉瘤（一种肌肉组织恶性肿瘤）密切相关。PAX7表达水平异常（过高或过低）均会破坏肌肉稳态：过表达可能促使卫星细胞异常增殖和癌变，同时抑制肌细胞终末分化；而表达不足则导致肌肉再生能力下降，加速肌萎缩。PAX7还与神经嵴细胞发育相关，其突变可能影响黑色素细胞和部分神经元的形成。在基因家族中，PAX成员均参与器官形成（如PAX6调控眼睛发育），但PAX7的特异性在于其专一性调控肌肉干细胞命运，这种功能分工使PAX家族成为发育生物学和再生医学的重要研究对象。

此基因是配对盒（PAX）家族的转录因子的成员。此基因家族成员通常包含配对盒结构域，八肽，以及一个成对型同源异型域。这些基因发挥胎儿的发育和肿瘤生长过程中的关键作用。配对盒7基因的具体功能不明，但推测由于这个基因与叉头域家族成员的融合已经与腺泡型横纹肌肉瘤相关的涉及抑制肿瘤。已发现该基因编码不同亚型三个抄本变形。 [由RefSeq的，2008年9月提供]

PAX7 is a member of the paired box (PAX) transcription factor family, a group of nine evolutionarily conserved proteins (PAX1–PAX9) that share a highly conserved DNA-binding domain enabling precise regulation of target gene expression during embryonic development, cellular differentiation, and tissue homeostasis. Distinct from other PAX family members, such as PAX6 which governs ocular development, PAX7 exhibits a specialized role in the regulation of skeletal muscle satellite cells, where it is highly expressed and serves as a master regulator of muscle stem cell identity. By activating downstream targets such as Myf5, PAX7 maintains the self-renewal capacity of satellite cells, preserves their undifferentiated state, and prevents premature myogenic commitment, thereby ensuring the stability of the stem cell reservoir necessary for muscle repair. Upon muscle injury, PAX7 drives the proliferation of activated satellite cells to facilitate regeneration, and its dysregulation has profound pathological consequences: loss-of-function mutations reduce satellite cell numbers or impair their function, leading to congenital myopathies or defective muscle regeneration, whereas overexpression, often resulting from chromosomal translocations, is strongly associated with rhabdomyosarcoma, a malignant tumor of muscle origin. Furthermore, abnormal PAX7 expression levels disrupt muscle homeostasis, with excessive expression promoting aberrant satellite cell proliferation and inhibiting terminal myocyte differentiation, while insufficient expression compromises regenerative capacity and accelerates muscle atrophy. Beyond its primary role in muscle biology, PAX7 is also implicated in neural crest cell development, where mutations may affect the formation of melanocytes and specific neuronal populations, underscoring its broader significance in developmental biology and its critical importance in regenerative medicine.

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