目的 對白蠟樹Fraxinus chinensis WRKY基因家族進行鑒定、生物信息學和密碼子偏好性分析。方法 基于白蠟樹全長轉錄組數據，利用生物信息學方法對其WRKY基因家族進行鑒定，并對其理化性質、系統(tǒng)發(fā)育、保守基序進行分析；基于白蠟樹葉片和枝皮的二代轉錄組數據，對白蠟樹WRKY基因家族的表達模式進行分析，并采用實時熒光定量PCR方法進行驗證；利用CodonW、EMBOSS等程序對密碼子偏好性進行分析，并進行最優(yōu)密碼子分析、中性繪圖、ENC-plot和PR2偏倚分析。結果 共鑒定得到49個WRKY轉錄因子，均為酸性、親水蛋白，編碼氨基酸數目為426～2 175，相對分子質量33 933.48～179 137.94，理論等電點4.91～5.27，不穩(wěn)定蛋白占比65.31%，預測均定位到細胞核；系統(tǒng)進化表明FcWRKY基因家族成員歸為Ⅰ（11個）、Ⅱ（30個）、Ⅲ（7個）大類以及2個特殊成員（FcWRKY23和FcWRKY37），其中第Ⅱ類分為Ⅱa（5個）、Ⅱb（5個）、Ⅱc（8個）、Ⅱd（7個）、Ⅱe（7個）5個亞類；Motif 1和Motif 2存在于所有的WRKY轉錄因子中，是其保守序列；二代轉錄組數據篩選到16個WRKY基因在葉片和枝皮中具有顯著差異表達，其中僅有FcWRKY11在枝皮中的表達量高于葉片。白蠟樹FcWRKYs偏好使用以A/U結尾的密碼子，并且偏好性較弱；確定了3個最優(yōu)密碼子，分別是CUU、AGG、和UAU；中性繪圖分析和ENC-plot分析均表明自然選擇是影響其密碼子偏好性的主要因素，PR2偏倚分析結果表明突變壓力亦影響其密碼子偏好性。結論 鑒定了白蠟樹WRKY基因，其中8個WRKY基因表達量與轉錄組學測序結果趨勢一致，為研究白蠟樹WRKY的基因功能奠定基礎。

Objective The aim of this study was to perform identification and bioinformatics and codon preference analysis of WRKY gene family of Fraxinus chinensis. Methods Based on the full-length transcriptome data of F. chinensis, the WRKY gene family was identified using bioinformatics methods and their physicochemical properties, phylogeny, conservative motifs were analyzed. Based on the second generation transcriptome data, expression patterns of WRKY gene family were analyzed and verified by real time fluorescence quantitative PCR. The codon bias was analyzed by CodonW and EMBOSS program, the optimal codon analysis, neutral plotting, ENC plot and PR2 bias analysis were also performed. Results A total of 49 WRKY genes were identified, all of them were acidic and hydrophilic proteins with an amino acid sequence varying from 426 to 2 175, molecular weight between 33 933.48 and 179 137.94, an isoelectric point between 4.91 and 5.27, unstable proteins accounted for 65.31%, and all of them were located in the nucleus. The phylogenetic tree showed that FcWRKY genes were assigned to Ⅰ (11),Ⅱ (30), Ⅲ (7) three categories and two special members (FcWRKY23 and FcWRKY37), the second category was divided into five subclass, including Ⅱa (5), Ⅱb (5), Ⅱc (8), Ⅱd (7) and Ⅱe (7); Conserved motif analysis showed that Motif 1 and Motif 2 were found in all WRKY transcriptional factors. A total of 16 significant differential expression WRKY genes in leaves and bark were identified, of which only FcWRKY11 was high expressed in bark than in leaves. The results of codon bias analysis showed that the FcWRKYs prefered to use codons ending in A/U weak codon usage. The optimal codons were identified, which were CUU, AGG and UAU; The results of neutrality plot analysis and ENC plot analysis indicated that natural selection was the main factor affecting its codon bias, PR2 bias analysis indicated that mutation pressure also had impact on codon preference. Conclusion It laid a theoretical foundation for the study of WRKY gene function in F. chinensis.

R286.12

陜西中醫(yī)藥大學秦藥特色資源研究開發(fā)重點實驗室開放課題（KF202326）；陜西省教育廳青年創(chuàng)新團隊建設科研計劃項目（21JP031）；陜西高校青年創(chuàng)新團隊資助項目（陜教［2019］90號）；陜西中醫(yī)藥大學校級科研課題（2023GP32）；云南省科技廳基礎研究專項資助項目（202101AU070005）