【摘要】：Argonaute蛋白是一類(lèi)與小RNA相互作用而起調(diào)控作用的蛋白。Argonaute蛋白在很多生物體包括植物和動(dòng)物中都有發(fā)現(xiàn),而且在所有生物體中都極其保守。Argonaute蛋白與小RNA結(jié)合,起基因調(diào)控的作用。它可以行核酸內(nèi)切酶的作用和RNA干擾作用,參與表觀(guān)遺傳調(diào)控、轉(zhuǎn)錄和翻譯的調(diào)控,因此還對(duì)胚胎發(fā)育過(guò)程有著重要作用。Argonaute蛋白在榕小蜂(膜翅目:小蜂總科)暫無(wú)相關(guān)研究報(bào)道。因此不同榕小蜂物種之間Argonaute蛋白基因的進(jìn)化關(guān)系,以及所有Argonaute蛋白基因經(jīng)受的選擇壓力等問(wèn)題是本研究所感興趣的。本論文首先通過(guò)設(shè)計(jì)簡(jiǎn)并引物來(lái)擴(kuò)增Argonaute蛋白的保守片段,再基于保守片段設(shè)計(jì)hiTAIL-PCR的引物來(lái)得到長(zhǎng)片段的Argonaute蛋白基因的序列。對(duì)于有基因組序列和(或)轉(zhuǎn)錄組數(shù)據(jù)的物種,如對(duì)葉榕傳粉榕小蜂Ceratosolen solmsi和非傳粉榕小蜂Walkerella sp.,還通過(guò)手工基因注釋和組裝并輔以實(shí)驗(yàn)驗(yàn)證獲得所有Argonaute蛋白基因的序列。結(jié)果一共獲得了來(lái)自七種榕小蜂的16條Argonaute蛋白基因的長(zhǎng)片段序列。針對(duì)所有已獲得的長(zhǎng)片段序列,用軟件MEGA6.0構(gòu)建基因樹(shù),然后用軟件PAML的codeml程序中的位點(diǎn)模型對(duì)榕小蜂的Argonaute蛋白基因所受的選擇壓力進(jìn)行分析。結(jié)果顯示:1,除對(duì)葉榕傳粉榕小蜂C.solmsi缺失PIWI蛋白亞家族的基因而只有AGO蛋白亞家族的Ago2、Ago2-like之外,其它榕小蜂物種都有2-4個(gè)Argonaute蛋白基因,既有AGO蛋白亞家族成員,也有PIWI蛋白亞家族成員;2,選擇壓力分析中,位點(diǎn)模型中的3對(duì)比較模型,M0/M3、M1/M2、M7/M8,都沒(méi)有檢測(cè)到正選擇位點(diǎn),而且各個(gè)分支都受到凈化作用。結(jié)合各基因所編碼蛋白的保守結(jié)構(gòu)域的預(yù)測(cè)結(jié)果,佐證了Argonaute蛋白的保守性。但是C.solmsi缺失PIWI蛋白亞家族的編碼基因也因此實(shí)在是一個(gè)暫時(shí)難以解釋的問(wèn)題。
[Abstract]:Argonaute protein is a class of proteins that interact with small RNAs and play the role of gene regulation in many organisms, including plants and animals, and it is extremely conserved in all organisms. It can perform endonuclease and RNA interference, participate in epigenetic regulation, transcription and translation regulation, Therefore, there are no related studies on the role of Argonaute protein in the development of Ficus figs (Hymenoptera: Cercidae). Therefore, the evolutionary relationship of Argonaute protein genes among different species of figs and the selection pressure of all Argonaute genes are of interest to this study. In this paper, degenerate primers were designed to amplify the conserved fragments of Argonaute protein, and then the primers of hiTAIL-PCR were designed to obtain the sequences of long fragments of Argonaute protein gene. For species with genomic sequences and / or transcriptome data, such as Ceratosolen solmsi and Walkerella sp. of fig pollinators, all Argonaute gene sequences were obtained by manual gene annotation and assembly and assisted with experimental verification. Results A total of 16 Argonaute gene fragments were obtained from seven fig wasps. For all the obtained long fragment sequences, the gene tree was constructed by using the software MEGA6.0, and then the selection pressure of the Argonaute protein gene of the fig wasp was analyzed by using the locus model in the codeml program of the software PAML. The results showed that except for the deletion of the PIWI protein subfamily gene to C. solmsi of the fig pollinated fig wasp and only the Ago2Ago2-like gene of the ago protein subfamily, all the other figs had 2-4 Argonaute protein genes, including the ago protein subfamily members. There are also PIWI protein subfamily members. In the selective pressure analysis, three pairs of comparison models of M0 / M3 / M1 / M2M7 / M8 have not detected positive selection sites, and each branch has been purified. The predicted results of conserved domain of the proteins encoded by each gene confirmed the conserved nature of Argonaute protein. However, the deletion of PIWI subfamily genes by C. solmsi is a difficult problem for the time being.
【學(xué)位授予單位】：河北大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：Q963

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 Hsueh-Yen Ku;Haifan Lin;;PIWI proteins and their interactors in piRNA biogenesis,germline development and gene expression[J];National Science Review;2014年02期

2 羅麗娟,施季森;一種DNA側(cè)翼序列分離技術(shù)——TAIL-PCR[J];南京林業(yè)大學(xué)學(xué)報(bào)(自然科學(xué)版);2003年04期

，

本文編號(hào)：2131860