共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
N S Yadav A Wierzbicki M Aegerter C S Caster L Prez-Grau A J Kinney W D Hitz J R Booth Jr B Schweiger K L Stecca et al. 《Plant physiology》1993,103(2):467-476
Arabidopsis thaliana T-DNA transformants were screened for mutations affecting seed fatty acid composition. A mutant line was found with reduced levels of linolenic acid (18:3) due to a T-DNA insertion. Genomic DNA flanking the T-DNA insertion was used to obtain an Arabidopsis cDNA that encodes a polypeptide identified as a microsomal omega-3 fatty acid desaturase by its complementation of the mutation. Analysis of lipid content in transgenic tissues demonstrated that this enzyme is limiting for 18:3 production in Arabidopsis seeds and carrot hairy roots. This cDNA was used to isolate a related Arabidopsis cDNA, whose mRNA is accumulated to a much higher level in leaf tissue relative to root tissue. This related cDNA encodes a protein that is a homolog of the microsomal desaturase but has an N-terminal extension deduced to be a transit peptide, and its gene maps to a position consistent with that of the Arabidopsis fad D locus, which controls plastid omega-3 desaturation. These Arabidopsis cDNAs were used as hybridization probes to isolate cDNAs encoding homologous proteins from developing seeds of soybean and rapeseed. The high degree of sequence similarity between these sequences suggests that the omega-3 desaturases use a common enzyme mechanism. 相似文献
11.
Krause K Maier RM Kofer W Krupinska K Herrmann RG 《Molecular & general genetics : MGG》2000,263(6):1022-1030
12.
13.
14.
The T-DNA tagged mutant gene of Arabidopsis thaliana, mei1, produces after meiosis an abnormal tetrad, consisting of five to eight microspores of varying sizes and DNA contents. Plant
DNA flanking the inserted T-DNA was isolated by inverse PCR. An approximately 16-kb DNA fragment spanning the T-DNA insertion
site was isolated by screening a wild-type genomic library, using the plant flanking DNA as a probe. Using RT-PCR and RNA
isolated from very young flower buds, a cDNA fragment was obtained. Nucleotide sequence comparison of the cDNA and the genomic
sequence in this region indicated a gene which contained two introns. The 5′ and 3′ splice sites of neither intron comply
with the :GU...AG: rule. In the mutant, the T-DNA had inserted into one of the introns. The deduced sequence of the MEI1 wild-type gene, which contains 89 amino acids, shows possible similarity with the human acrosin-trypsin inhibitor, HUSI-II,
and is about the same size. Two wild-type DNA fragments, both extending over the T-DNA insertion site, were introduced into
mutant plants by Agrobacterium-mediated transformation and plants were selected for both hygromycin and kanamycin resistance. Several independent male-fertile
transformants were obtained with one of the DNA fragments. The fragment showing complementation of the mutant phenotype indicated
that the sequence with similarity to the acrosin-trypsin inhibitor is MEI1. Within the 16-kb genomic fragment two other genes were identified; one showed no overall similarity to any protein sequence
in the database and the other had almost complete identity with an Arabidopsis-transcribed sequence tag with similarity to ACC oxidase. Double mutants between mei1 and qrt1 were made, permitting better characterization of the mei1 phenotype because the individual microspores continued to be held together after callose dissolution.
Received: 21 April 1998 / Revision accepted: 11 June 1998 相似文献
15.
16.
17.
18.
The homozygous T-DNA mutants of AtCAL1 (Rat1) and AtCAL2 (Rat2) were obtained. The double mutant of Rat2/Rat1RNAi was constructed which showed obvious late-flowering phenotype from others. The expression of various flowering-related genes
was studied among mutants and wild-type plants by quantitative RT–PCR. The double mutant plants showed the shortest root length
compared with T-DNA insertion mutants and wild type plants under red light, blue light, and white light. The double mutants
showed hypersensitivity to NaCl and ABA. However, these mutants had no effect on stomatal closure by ABA. 相似文献
19.