条斑紫菜藻红、藻蓝蛋白α和β亚基基因序列测定及分析

为了获得江苏吕泗的条斑紫菜藻红蛋白α(Pea)和β(Peb)亚基、藻 蓝蛋白α(Pca)和β(Pcb)亚基基因的DNA序列，本文对其基因进行了克隆、 序列测定及分析.根据已发表的基因序列(DQ666487.1)设计引物，对提取自 条斑紫菜叶状体的DNA进行PCR和电泳鉴定，产物经测序证实获得藻红蛋白 序列1 357 bp (HM008263.1)和藻蓝蛋白序列1 335 bp (HM008262.1).上述 两段序列与已报道的条斑紫菜相关序列(DQ666487.1)同源性均为99％，与 其它几种紫菜相关序列同源性为88％～98％.两段序列均采用多顺反子转录 策略，排布顺序为5′Untranslated Regions(UTR)- Peb -间隔区- Pea -3 ′UTR 和 5′UTR- Pcb -间隔区- Pca -3′UTR.文中对基因翻译所得氨基 酸序列做了理化参数、功能位点及空间构型的预测.基于对序列开放阅读框 、启动子、Shine-Dalgarno (SD)序列的分析，本文对条斑紫菜分类地位进 行了讨论.

Sequencing and Analysis of α and β Subunit Gene of Phycoerythrin and Phycocyanin from Porphyra yezoensis

We cloned the full-length cDNAs of the phycoerythrin α (Pea), β (Peb) subunit and the phycocyanin α (Pca) and β (Pcb) subunit from Porphyra yezoensis in Lvsi city, Jiangsu Province. The total DNA was extracted for PCR and electrophoresis using the primers derived from the Genbank sequence DQ666487.1 of Porphyra yezoensis.homolog. The phycoerythrin of 1357bp (HM008263.1) and phycocyanin of 1335bp (HM008262.1) were obtained, which shared a. 99% homology to DQ666487.1 and 88-98% homology to other species of Porphyra. Two open reading frames (ORF) was identified for each protein-coding cDNA that was arranged as 5′UTR- Peb -intergenic region- Pea-3′UTR, and 5′ UTR- Pcb -intergenic region- Pca -3′UTR. The amino acid sequences translated from the cloned sequences were analyzed for functional domains, spatial configuration of the subunits, the taxonomy with Porphyra yezoensis, The promoter and the Shine- Dalgarno (SD) sequences of the cloned genes were also discussed.