茎瘤芥BjMYB1基因的克隆、表达与遗传转化研究

MYB转录因子广泛地参与了植物细胞分化、细胞周期的调节,激素和环境因子应答等过程。本研究根据茎瘤芥转录组测序筛选获得了一个MYB基因片段。通过RACE的方法,克隆得到了两条长度分别为975bp和864bp的全长序列,分析发现可能为茎瘤芥MYB基因的两种不同选择性拼接形式,并命名为BjMYB1-3和BjMYB1-4。对BjMYB1-3和BjMYB1-4做组织表达分析,发现这两个转录本在茎中特异表达。针对BjMYB1-3和BjMYB1-4的亚细胞定位分析,显示BjMYB1-4定位于细胞核,BjMYB1-3部分定位于细胞核。构建BjMYB-3和BjMYB1-4的超表达载体转化拟南芥,结果显示超表达转化的植株会使拟南芥提前抽薹和开花,说明BjMYB1-3和BjMYB1-4在植株的生长发育过程中起着一定作用,为进一步阐明茎瘤芥BjMYB1基因的功能奠定了基础。     

Discovery of mitochondrial chimeric-gene associated with cytoplasmic male sterility of HL-rice

The mitochondrial genome libraries of HL-type sterile line (A) and maintainer line (B) have been constructed. Mitochondrial gene, atp6 , was used to screen libraries, due to the different Southern and Northern blot results between sterile and maintainer line. Sequencing analysis of positive clones proved that there were two copies of atp6 gene in sterile line and only one in maintainer line. One copy of atp6in sterile line was same to that in maintainer line; the other showed different flanking sequence from the 49th nucleotide downstream of the termination codon of atp6 gene. A new chimeric gene, orfH79 , was found in the region. orfH79 had homology to mitochondrial gene coxⅡ and orfH79, and was special to HL-sterile cytoplasm.     

Sequence analysis of the gene correlated with cytoplasmic male sterility (CMS) in rape-seed (Brassica napus) Polima and Shaan 2A

orf224 is a CMS-related mitochondrial gene discovered in Polima cytoplasm. Shaan 2A CMS line is the parent of the first rapeseed hybrid cultivar Qinyou No. 2that has been grown in many regions of China. In this work,genomic DNA of Polima CMS line and Shaan 2A CMS line were used as templates, two primers of specific oligonucleoamplification fragments were cloned into pGEM-T Easy vectors and DNA sequences were determined. The CMSassociated gene, orf224-1 present in Shaan 2A CMS line, has a sequence highly homologous to the orf224 of the Polima CMS line, except for one nucleotide at position +398. There were only one base (AAC→AGC) and one amino acid (Asn →Ser) differences between the two. The homologies of the two sequences in nucleotide and. amino acid were 99.9 % and 99.6%, respectively. It is concluded that orf224 in Polima CMS line and orf224-1 of Shaan 2A CMS line are the allele at the same locus in mitochondria.``     

Sequence analysis of the gene correlated with cytoplasmic male sterility (CMS) in rape-seed (Brassica napus) Polima and Shaan 2A

orf224 is a CMS-related mitochondrial gene discovered in Polima cytoplasm. Shaan 2A CMS line is the parent of the first rapeseed hybrid cultivar Qinyou No. 2 that has been grown in many regions of China. In this work, genomic DNA of Polima CMS line and Shaan 2A CMS line were used as templates, two primers of specific oligonucleotides at 5′ and 3′ ends were used, PCR was performed, the amplification fragments were cloned into pGEM-T Easy vectors and DNA sequences were determined. The CMS-associated gene, orf224-1 present in Shaan 2A CMS line, has a sequence highly homologous to the orf224 of the Polima CMS line, except for one nucleotide at position +398. There were only one base (AAC→AGC) and one amino acid (Asn →Ser) differences between the two. The homologies of the two sequences in nucleotide and amino acid were 99.9% and 99.6%, respectively. It is concluded that orf224 in Polima CMS line and orf224-1 of Shaan 2A CMS line are the allele at the same locus in mitochondria.