国际医学寄生虫病杂志
國際醫學寄生蟲病雜誌
국제의학기생충병잡지
INTERNATIONAL JOURNAL OF MEDICAL PARASITIC DISEASES
2015年
2期
67-73
,共7页
日本血吸虫%组蛋白%进化分析%基因倍增
日本血吸蟲%組蛋白%進化分析%基因倍增
일본혈흡충%조단백%진화분석%기인배증
Schistosoma japonicum%Histone%Evolutionary analysis%Gene duplication
目的 从日本血吸虫(Schistosoma japonicum)组蛋白的基因家族进化方面人手,对其基因家族的分子系统发育、共线性关系和基因倍增模式进行分析. 方法 下载3种主要致病血吸虫的全基因组序列数据及外源物种基因序列,经Blastp软件比对找出组蛋白各家族基因序列,经多序列比对构建系统进化树,计算选择压力指数(Ka/Ks).使用基因序列与基因组比对并定位,分析同源基因的共线性关系. 结果 日本血吸虫基因组共包含组蛋白基因38条,分为5个子家族,分布在25个scaffold上.通过进化树分析共检测到基因倍增事件34次,推定基因丢失事件17次,其中H3和H4的倍增早在血吸虫物种形成之前已经完成.日本血吸虫组蛋白的倍增机制主要是DNA复制性转座,使得组蛋白在进化保守的同时还出现了更特异性的分化,从而携带更多组蛋白密码或其他修饰信息以应对较复杂的生命周期. 结论 日本血吸虫的组蛋白各子家族多数倍增事件发生在从血吸虫亚洲起源后到进入非洲分化出曼氏血吸虫之前的这段时间内,表明基因倍增是血吸虫应对环境压力的重要手段.日本血吸虫的组蛋白倍增完全来自于DNA序列的复制性转座,且净化选择占主导因素,表明增强适应性的功能分化是基因进化最主要的驱动力.
目的 從日本血吸蟲(Schistosoma japonicum)組蛋白的基因傢族進化方麵人手,對其基因傢族的分子繫統髮育、共線性關繫和基因倍增模式進行分析. 方法 下載3種主要緻病血吸蟲的全基因組序列數據及外源物種基因序列,經Blastp軟件比對找齣組蛋白各傢族基因序列,經多序列比對構建繫統進化樹,計算選擇壓力指數(Ka/Ks).使用基因序列與基因組比對併定位,分析同源基因的共線性關繫. 結果 日本血吸蟲基因組共包含組蛋白基因38條,分為5箇子傢族,分佈在25箇scaffold上.通過進化樹分析共檢測到基因倍增事件34次,推定基因丟失事件17次,其中H3和H4的倍增早在血吸蟲物種形成之前已經完成.日本血吸蟲組蛋白的倍增機製主要是DNA複製性轉座,使得組蛋白在進化保守的同時還齣現瞭更特異性的分化,從而攜帶更多組蛋白密碼或其他脩飾信息以應對較複雜的生命週期. 結論 日本血吸蟲的組蛋白各子傢族多數倍增事件髮生在從血吸蟲亞洲起源後到進入非洲分化齣曼氏血吸蟲之前的這段時間內,錶明基因倍增是血吸蟲應對環境壓力的重要手段.日本血吸蟲的組蛋白倍增完全來自于DNA序列的複製性轉座,且淨化選擇佔主導因素,錶明增彊適應性的功能分化是基因進化最主要的驅動力.
목적 종일본혈흡충(Schistosoma japonicum)조단백적기인가족진화방면인수,대기기인가족적분자계통발육、공선성관계화기인배증모식진행분석. 방법 하재3충주요치병혈흡충적전기인조서렬수거급외원물충기인서렬,경Blastp연건비대조출조단백각가족기인서렬,경다서렬비대구건계통진화수,계산선택압력지수(Ka/Ks).사용기인서렬여기인조비대병정위,분석동원기인적공선성관계. 결과 일본혈흡충기인조공포함조단백기인38조,분위5개자가족,분포재25개scaffold상.통과진화수분석공검측도기인배증사건34차,추정기인주실사건17차,기중H3화H4적배증조재혈흡충물충형성지전이경완성.일본혈흡충조단백적배증궤제주요시DNA복제성전좌,사득조단백재진화보수적동시환출현료경특이성적분화,종이휴대경다조단백밀마혹기타수식신식이응대교복잡적생명주기. 결론 일본혈흡충적조단백각자가족다수배증사건발생재종혈흡충아주기원후도진입비주분화출만씨혈흡충지전적저단시간내,표명기인배증시혈흡충응대배경압력적중요수단.일본혈흡충적조단백배증완전래자우DNA서렬적복제성전좌,차정화선택점주도인소,표명증강괄응성적공능분화시기인진화최주요적구동력.
Objective To investigate the molecular phylogeny,gene collinear relation and gene duplication mode of the histone gene family evolution in Schistosoma japonicum.Methods The latest version of coding gene sequences and protein sequence of three schistosomes including S.japonicum,S.mansoni and S.haematobium were downloaded from SchistoDB.The histone gene sequences were identified in Blastp and aligned in ClustalW2.1.After constructing the phylogenetic trees,the Ka/Ks value was calculated and the synteny relationships were analyzed.Results There are totally 38 histone genes in the S.japonicum genome,divided into 5 subfamilies and distributed in 25 scaffolds.By reconstruction of phylogenetic trees,34 gene duplications events and 17 gene loss events were detected.The H3 and H4 gene duplications completed even before speciation.The primary means of the gene duplication events is DNA replicative transposition,which giving histone genes more specific differentiation while keeping conservative evolution.Thus these genes can carry extra histone codes in reaction to complex life cycle.Conclusions The phylogenetic trees showed that the divergence of histone gene family was earlier than the divergence of schistosomes.However,there are 34 gene duplication and 17 gene loss events happened during the past 20 million years.It illustrates even the most conservative gene family is dynamic in evolution.Most of the duplication events took place between the time period from the schistosomes origined in Asia to divergence in Africa,demonstrating that duplication is the important instruments to response to environmental stress.Moreover,Ka/Ks values show that the functional differentiation of strengthen adaptability is the driving force behind gene evolution.
