IL12A gene transcription and translation

Interleukin-35 (IL35) is a complex conformed by Interleukin-12 subunit alpha (IL12A) and Interleukin-27 subunit alpha (IL27). IL35 can induce heterodimers of Interleukin-6 receptor beta precursor (IL6ST) and Interleukin-12 receptor beta 2 (IL12RB2). Consequently, heteromeric Signal transducer and activator of transcription 1-alpha/beta (STAT1) and Signal transducer and activator of transcription 4 (STAT4) are phosphorylated. Subsequently, this STAT1:STAT4 complex can translocate into the nucleus and bind to promoter regions of IL12A thereby facilitating the protein expression. Thus, by inducing the expression of itself, a positive feedback regulation is achieved in the IL35 signalling pathway. This is a black box event because the intermediate steps of IL12A transcription/translation are omitted.

白介素-35（IL35）由白介素-12亚基α（IL12A）和白介素-27亚基α（IL27）组成的一种复杂结构。IL35能够诱导白介素-6受体β前体（IL6ST）与白介素-12受体β2（IL12RB2）形成的异源二聚体。进而，异源性的信号转导和转录激活因子1-α/β（STAT1）与信号转导和转录激活因子4（STAT4）发生磷酸化。随后，此STAT1:STAT4复合物可转移至细胞核并与IL12A的启动子区域结合，从而促进蛋白质的表达。因此，通过诱导自身表达，实现了IL35信号通路中的正反馈调节。这是一个黑盒事件，因为IL12A转录/翻译的中间步骤被省略。