The proteins P53 and Mdm2 (murine double minute 2) play a prominent role in preventing the induction of uncontrolled apoptosis in numerous cell types. To better understand their potential roles during gonadal development in Monopterus albus, p53 and mdm2 homologues were isolated and characterized, and their mRNA expression patterns in developing gonadal and ovarian tissue incubated with H₂O₂ in vitro were analysed. The open reading frames (ORFs) of p53 and mdm2 consisted of 1125 and 1497 base pairs (bp), respectively. A multiple amino acid residue alignment analysis showed that p53 and Mdm2 harboured the typical conserved domains of their gene families. Phylogenetic analysis also demonstrated that the Mdm2 of M. albus exhibited high sequence similarity with Lates calcarifer; however, the p53 sequences of the Neoteleostei, including M. albus, were distinct from those of the Euteleostei and other vertebrates. Quantitative real-time PCR revealed that p53 and mdm2 were mainly expressed in the ovary; their expression was significantly increased in the previtellogenic stage, was maintained at the increased level thereafter, showed a second increase in the early intersexual stage, and then decreased with the natural sex change from female to male. After incubation with H₂O₂, the expression patterns of p53 and mdm2 in ovarian fragments were similar to that of the apoptotic molecular marker caspase3, showing a significant increase at 1 h post incubation (hpi), a decrease after 2 hpi, and then a return to significantly upregulated levels at 4 hpi and 8 hpi. In addition, p53, mdm2 and caspase3 were strongly correlated. These results will be useful for further studies on the function and regulation of p53 and Mdm2 during gonadal development in Monopterus albus, particularly in the ovary.

蛋白P53和Mdm2（鼠类双分钟2）在防止多种细胞类型中诱导不受控制的凋亡中起着重要作用。为了更好地了解它们在Monopterus albus的性腺发育过程中的潜在作用，分离并鉴定了p53和mdm2同源物，并分析了它们在体外与H ₂ O ₂ 孵育的发育中的性腺和卵巢组织中的mRNA表达模式。p53和mdm2的开放阅读框（ORF）分别由1125和1497个碱基对（bp）组成。多个氨基酸残基比对分析表明，p53和Mdm2具有其基因家族的典型保守结构域。系统发育分析还证明的Mdm2的黄鳝表现出与高序列相似鲈calcarifer ; 然而，Neoteleostei的p53基因序列，包括黄鳝，是来自那些Euteleostei和其他脊椎动物的不同。实时定量PCR显示p53和mdm2主要在卵巢中表达；它们的表达在前玻璃体形成阶段显着增加，此后保持在增加的水平，在两性早期开始出现第二次增加，然后随着自然性别从雌性变为雄性而降低。用H ₂ O ₂孵育后，卵巢片段中p53和mdm2的表达模式与凋亡分子标记caspase3相似，在孵育后1 h（hpi）显着增加，在2 hpi后降低，然后在4 hpi和8 hpi时恢复到明显上调的水平。另外，p53，mdm2和caspase3是高度相关的。这些结果将有助于进一步研究黄opter，特别是卵巢中性腺发育过程中p53和Mdm2的功能和调控。