Sinnemann S J, Andrésson O S, Brown D W, Miao V P
TerraGen Discovery, Inc., UBC, Vancouver British Columbia, Canada.
Curr Genet. 2000 May;37(5):333-8. doi: 10.1007/s002940050536.
A pyrG gene, encoding orotidine 5'-monophosphate decarboxylase, was cloned from a phage library derived from the lichen Solorina crocea. Phylogenetic analysis and a survey of geographically well-separated specimens were used to verify that the gene represented the fungal component of the lichen. Both coding and upstream sequences of S. crocea pyrG exhibited features typical of fungal genes. A 132-bp intron interrupting the coding region between nucleotides 157 and 288 was confirmed by RT-PCR and sequencing. Transformation of Aspergillus nidulans with S. crocea pyrG, controlled by either its native promoter or the A. nidulans trpC promoter, resulted in uridine-independent strains that exhibited appreciable growth only at 24 degrees C. Southern analysis indicated multiple integrations of S. crocea pyrG. These results demonstrate that heterologous expression may be used to investigate genes from lichens.
从地衣 Solorina crocea 的噬菌体文库中克隆出一个编码乳清苷 5'-单磷酸脱羧酶的 pyrG 基因。系统发育分析以及对地理上相隔甚远的标本进行的调查，用于验证该基因代表了地衣的真菌成分。Solorina crocea pyrG 的编码序列和上游序列均表现出真菌基因的典型特征。通过 RT-PCR 和测序证实，一个 132 碱基对的内含子打断了第 157 至 288 位核苷酸之间的编码区。用 Solorina crocea pyrG 转化构巢曲霉，该基因由其天然启动子或构巢曲霉 trpC 启动子控制，得到了不依赖尿苷的菌株，这些菌株仅在 24℃时表现出明显生长。Southern 分析表明 Solorina crocea pyrG 发生了多次整合。这些结果表明，异源表达可用于研究地衣中的基因。
