摘要
以6种不同颜色的坛紫菜(Pyropia haitanensis)品系为研究材料,通过生理指标测定和转录组测试分析,对坛紫菜色素突变体产生的原因进行初步研究。根据色度值将6个品系划分为红黄组和绿组,其中:红黄组包括3个色素突变品系(红色、橘色和紫色)和1个野生品系,绿组包括2个色素突变品系(棕绿色和翠绿色)。进一步研究发现:1)红黄组品系的平均藻红蛋白(PE)含量比绿组高1倍,但两组藻体在藻蓝蛋白(PC)和别藻蓝蛋白(APC)含量上没有显著差异。2)红黄组藻体的平均叶绿素(Chl a)含量比绿组低35%,这导致红黄组藻体的PE/Chl a含量比绿组高1.7倍。3)红黄组藻体藻胆蛋白合成关键基因血红素氧化酶(HMOX1)和铁氧还蛋白氧化还原酶(HY2)的表达水平高于绿组。4)两组内不同品系间在色素合成关键基因的表达上具有显著差异。其中,叶绿素和藻胆蛋白合成的关键基因hemA的表达水平上调,促进更多色素的合成;叶绿素合成关键基因Mg-鳌合酶亚基和CHLG表达水平上调,调控藻体合成更多Chl a,使得藻体呈绿色;而HMOX1和HY2明显上调,促进血红素合成胆绿素,最终提高PE含量,使藻体偏红色。以上结果说明,坛紫菜藻胆蛋白和叶绿素合成通路中关键基因的差异表达可能导致藻体PE/Chl a含量比的不同,进而产生不同颜色的突变体。
In this study,to investigate the formation reason of pigment mutants of Pyropia haitanensis,six strains with different color were used as research materials through physiological and transcriptomic analysis.Based on the chroma values,six strains were divided into a red-yellow group and a green group.The former group included three pigment mutants(Red,Orange and Purple)and a wild strain,the latter group included two pigment mutant strains(Brown-Green and Olive-Drab).This study found that the average content of phycoerythrin(PE)in the red-yellow group was one time higher than the green group,but there was no significant difference in the content of phycocyanin(PC)and allophycocyanin(APC)between the two groups.In contrast,the average content of Chl a in the red-yellow group was 35%lower than that of the green group,which resulted in that the ratio of PE/Chl a in the red-yellow group was 1.7 times higher than the green group.In addition,the expression levels of heme oxygenase 1(HMOX1)and ferredoxin oxidoreductase(HY2),the key genes of phycobiliprotein synthesis,were higher in the red-yellow group than in the green group,different strains within the two groups showed significant differences in the expression of the key genes for pigments synthesis.Among them,the expression level of hemA,the key gene for chlorophyll and phycobilin synthesis,was up-regulated,which accelerated the synthesis of plant pigments;the expression levels of CHLG and magnesium chelatase were up-regulated,which accelerated the synthesis of chlorophyll;the expression of HMOX1 and HY2 were significantly up-regulated,which improved the synthesis of bilirubin from Heme,and then elevated the contents of PE and determined the chroma values.The above results indicated that the expressions of the key genes of the pigments synthesis pathways in the P.haitanensis resulted in different ratios of PE/Chl a,which thus determined the colors.
作者
连跃斌
许凯
王文磊
徐燕
纪德华
陈昌生
谢潮添
LIAN Yuebin;XU Kai;WANG Wenlei;XU Yan;JI Dehua;CHEN Changsheng;XIE Chaotian(Fisheries College,Jimei University,Xiamen 361021,China)
出处
《集美大学学报（自然科学版）》
CAS
2020年第3期161-170,共10页
Journal of Jimei University：Natural Science
基金
福建省自然科学基金青年创新基金(2018J05069)
福建省科技计划区域发展示范项目(2017N3016)
现代农业产业技术体系专项资金资助项目(CARS-50)。
关键词
坛紫菜
藻胆蛋白
叶绿素A
转录组
色素突变体
Pyropia haitanensis
phycobiliprotein
chlorophyll a
transcriptome
pigment mutants
