Isolation and analysis of anther-expressed genes E8-6 and Clone 7 from heat-tolerant tomato
Date Issued
2006
Date
2006
Author(s)
Chen, Yu-Huei
DOI
zh-TW
Abstract
Tomatoes incur poor growth and fruit set under hot-dry or hot-wet season in tropics and subtropics, which is a major bottleneck impeding summer production in Taiwan. Recent studies concluded that impairment of pollen and anther development by elevating temperature contributes to decrease fruit set in tomatoes. AVRDC (Asia Vegetable Research and Development Center) has bred serial heat-tolerant tomatoes, yet the molecular mechanism of heat tolerance is still unclear. To analyze these heat-tolerant genes that affect pollen viability, Suppression Subtractive Hybridization (SSH) was used to isolate cDNA fragments from the anther of heat-tolerant tomato CL5915 at high temperature, 35oC. By analyzing temperature effects of these genes from the heat-induced cDNA library using Real-time PCR and Northern blot, Clone 8’ and Clone 7 were selected for further studies. Compared with NCBI nucleotide database, these genes are suggested to be E8-6 and a Lycopersicon esculentum clone 133497F, respectively. E8-6 is a Tomato E8 protein homolog with a related isopenicillin N synthase and related dioxygenases domain, while clone 133497F is presumed to be an Arabidopsis beta-ureidopropionase homolog with a CN hydrolase conserved domain. Several transgenic tomatoes were then created so that overexpression of E8-6 and Clone 7 was built in the heat-sensitive tomato L4783, while knock-down expression was made in heat-tolerant tomato CL5915 in order to characterize the functions of E8-6 and Clone 7. Furthermore, the promoters of E8-6 were isolated from CL5915 and L4783. There is no difference of cis-acting and responsive element between CL5915 and L4783, and both of them have two heat shock elements, indicating that E8-6 may be induced by elevated temperature. Subsequently, the GUS reporter gene driven by E8-6 promoter expressed in Arabidopsis was analyzed. The expression pattern detected by GUS staining indicated that E8-6 promoter expresses in sepal, filament, and stigma of flowers.
Subjects
番茄
tomato
Type
other