TNF receptor-associated factor 6 (TRAF6) is a signal transducer, which plays a pivotal role in triggering a variety of signalling cascades. Here, we cloned and identified the TRAF6 gene from the King pigeon. The open reading frame sequence of pigeon TRAF6 (piTRAF6) is 1638 bp long and encodes a 545 aa protein, including a low-complexity domain, RING finger, Zinc finger, coiled coil domain, and meprin and TRAF homology domain. The aa sequence of piTRAF6 shared a strong identity with that of other birds. PiTRAF6 transcripts were broadly expressed in all the tested tissues; piTRAF6 levels were the highest and lowest in the heart and stomach, respectively. Overexpression of piTRAF6 activated NF-κB in a dose-dependent manner and induced IFN-β expression. Upon piTRAF6 knockdown by small interfering RNAs, NF-κB activation was markedly inhibited in HEK293T cells. The expression of piTRAF6, as well as pro-inflammatory cytokines and antiviral molecules, were obviously increased after TLR ligand stimulation and Newcastle disease virus or Salmonella Pullorum inoculation. These results suggest that piTRAF6 may play a key immunoregulatory role in the innate immune response against viral and bacterial infections.

TNF 受体相关因子 6 (TRAF6) 是一种信号转导器，在触发多种信号级联反应中起关键作用。在这里，我们从王鸽中克隆并鉴定了 TRAF6 基因。鸽子TRAF6（piTRAF6）的开放阅读框序列长1638 bp，编码545个氨基酸的蛋白质，包括低复杂度域、环指、锌指、卷曲螺旋域以及meprin和TRAF同源域。piTRAF6 的 aa 序列与其他鸟类的序列具有很强的同一性。PiTRAF6 转录本在所有测试组织中广泛表达；piTRAF6 水平分别在心脏和胃中最高和最低。piTRAF6 的过表达以剂量依赖性方式激活 NF-κB 并诱导 IFN-β 表达。在 piTRAF6 被小干扰 RNA 敲低后，NF-κB 活化在 HEK293T 细胞中被显着抑制。piTRAF6 的表达以及促炎细胞因子和抗病毒分子在 TLR 配体刺激和新城疫病毒或沙门氏菌接种。这些结果表明 piTRAF6 可能在针对病毒和细菌感染的先天免疫反应中发挥关键的免疫调节作用。