摘要：
Arabinogalactan proteins (AGPs) are a large family of highly glycosylated of hydroxyproline-rich glycoproteins that play important roles in plant growth, development, and signal transduction. A cDNA encoding a putative classical AGP named GhH6L was isolated from cotton fiber cDNA libraries, and the deduced protein contains 17 copies of repetitive motif of X-Y-proline-proline-proline (where X is serine or alanine and Y is threonine or serine). Northern blotting analysis and quantitative RT-PCR results showed that it was preferentially expressed in 10 days post-anthesis (dpa) fibers and was also developmentally regulated. A promoter fragment was isolated from cotton (Gossypium hirsutum) by genome walking PCR. Expression of beta-glucuronidase (GUS) gene under the GhH6L promoter was examined in the transgenic Arabidopsis plants; only petiole and pedicel were stained, no staining was detected in other tissues. Subcellular localization indicated that GhH6L was localized to the plasma membrane and in the cytoplasm. These data further our understanding of GhH6L as well as shed light on functional insight to GhH6L in cotton.
作者机构：
[Li, Juan] College of Life Sciences, Central China Normal University, Wuhan, Hubei, China;[Liu, Yong-Ding] Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China;[Zhang, Cheng-Cai] College of Life Sciences and Technology, Huazhong Agricultural University, Wuhan, Hubei, China;[Xu, Wen-Liang] College of Life Sciences, Central China Normal University, Wuhan, Hubei, China<&wdkj&>Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China
通讯机构：
[Liu Yong-ding] I;Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei, China
摘要：
ThefecC gene encoding a putative iron (III) dicitrate transporter was cloned from nitrogen-fixing cyanobacteriumAnabaena sp. PCC 7120, and inactivated. The mutant grows normally in medium with NO 3 ? , NH 4 + or without combined nitrogen. But in iron-deficient medium, the mutant grows slowly. Photosynthetic properties were compared between the mutant and the wildtype strain, the content of photosynthetic pigments in the mutant is lower than that of the wild-type. The results of RT-PCR experiments show that thefecC gene is expressed under iron-deficient conditions, but is not expressed under iron-replete conditions. These results revealed thatfecC gene product is required for optimal growth under iron-deficient conditions inAnabaena sp. PCC 7120. Key words Anabaena sp. PCC 7120 - fecC - iron deficiency - photosynthetic properties - expression CLC number Q 933 Foundation item: Supported by the National Natural Sciences Foundation of China (30070154), the Frontier Science Projects Program of the Institute of Hydrobiology, the Chinese Academy of Sciences (220316), State Key Project on Cyanobacterial Bloom Control in Lake Dianchi (K99-05-35-01) Biography: XU Wen-liang (1974-), male, Ph. D, research direction: molecular genetics of cyanobacteria.
摘要：
用一定浓度范围(2.5-5.0mg/L)的超氧化物歧化酶模型化合物(Superoxide dismutase model compound,SODMC)以浸种和喷洒相结合的方式处理水稻幼苗,以幼苗二叶一心期为低温胁迫期,结果表明处理能够维持低温胁迫后水稻幼苗体内较高的SOD活性,较低的MDA含量和电解质渗漏,显示SODMC处理对低温胁迫苗的保护作用,然而稍高浓度(7.5mg/L)的SODMC处理则有一定的毒害作用。
