Amaryllidaceae, a monocot plant family, consists of many important ornamental bulb flower species. Chinese narcissus （Narcissus tazetta var. chinensis Roem）, its flowers developed at high temperatures and bloomed at...Amaryllidaceae, a monocot plant family, consists of many important ornamental bulb flower species. Chinese narcissus （Narcissus tazetta var. chinensis Roem）, its flowers developed at high temperatures and bloomed at lower temperatures during the Chinese Spring Festival, is a traditional Chinese flower with high economic and ornamental value. To study its flower development, a full length cDNA containing MADS box domain from narcissus was isolated by a reverse transcription polymerase chain reaction （RT-PCR） with degenerate oligo-nucleotide primers derived from a conserved MADS- and K-box domain sequence. The 5＇ and the 3＇ regions of the gene were amplified using the PCR protocol for the rapid amplification of cDNA ends （RACE）. The 690 bp open reading frame encodes 230 amino acid residues. A comparison of the deduced amino acid sequence of NTAG with the sequence of other MADS box proteins showed 91.3% amino acid identities with HAG （Hyacinthus orientalis）. Sequence analysis and alignment showed significant similarity with other AG homologues. RNA blot analysis indicated that the narcissus NTAG gene was expressed only in reproductive organs, especially in stamens and carpels. These results indicated that the NTAG gene was an AG homologue and that the AG genes appeared to be structurally and functionally conserved between dicots and monocots.展开更多
: For the sake of providing some important information relevant to the study of the molecular mechanism of genic male sterility in plants, gene differential expression in flower buds at different developmental stages,...: For the sake of providing some important information relevant to the study of the molecular mechanism of genic male sterility in plants, gene differential expression in flower buds at different developmental stages, as well as in rosette leaves, florescence leaves, and scapes was analyzed using cDNA amplified fragment length polymorphism (cDNA-AFLP) in the genic male sterile A and fertile B line of Chinese cabbage pak-choi. Following amplification of 125 pairs of primer combinations, 11 differential fragments were obtained, of which eight were from the B line and the other three were from the A line. Of 11 differential fragments, four were verified by Northern hybridization that were expressed preferentially in fertile flower buds. Results of GenBank BLAST showed that one fragment was with unknown function, whereas the other fragments have strong nucleotide sequence similarities with the polygalacturonase (PG) gene, the pectinesterase (PE) gene, and the polygalacturonase inhibitory protein (PGIP4) gene. Only full-length cDNA from the differential fragment BcMF-A18T16-1 was amplified by rapid amplification of cDNA ends (RACE) and Northern analysis showed that this fragment was expressed only in medium and large-sized flower buds of the B line. The full-length cDNA, designated as BcMF2 (Brassica campestris Male Fertile 2), was 1 485 bp long and was composed of a 1 263-bp open reading frame, which had 83% nucleotide similarity to a PG gene from Arabidopsis encoding polygalacturonase. Analysis of the basic structure of the protein revealed that it had one polygalacturonase active site (RVTCGPGHGLSVGS) at 256th site of amino acids and was classified as being a member of family 28 of the glycosyl hydrolases. The role of the BcMF2 gene on microspore development is discussed in the present paper.展开更多
文摘Amaryllidaceae, a monocot plant family, consists of many important ornamental bulb flower species. Chinese narcissus （Narcissus tazetta var. chinensis Roem）, its flowers developed at high temperatures and bloomed at lower temperatures during the Chinese Spring Festival, is a traditional Chinese flower with high economic and ornamental value. To study its flower development, a full length cDNA containing MADS box domain from narcissus was isolated by a reverse transcription polymerase chain reaction （RT-PCR） with degenerate oligo-nucleotide primers derived from a conserved MADS- and K-box domain sequence. The 5＇ and the 3＇ regions of the gene were amplified using the PCR protocol for the rapid amplification of cDNA ends （RACE）. The 690 bp open reading frame encodes 230 amino acid residues. A comparison of the deduced amino acid sequence of NTAG with the sequence of other MADS box proteins showed 91.3% amino acid identities with HAG （Hyacinthus orientalis）. Sequence analysis and alignment showed significant similarity with other AG homologues. RNA blot analysis indicated that the narcissus NTAG gene was expressed only in reproductive organs, especially in stamens and carpels. These results indicated that the NTAG gene was an AG homologue and that the AG genes appeared to be structurally and functionally conserved between dicots and monocots.
基金国家自然科学基金，the Key Sci-Technology Project of Zhejiang Province,China
文摘: For the sake of providing some important information relevant to the study of the molecular mechanism of genic male sterility in plants, gene differential expression in flower buds at different developmental stages, as well as in rosette leaves, florescence leaves, and scapes was analyzed using cDNA amplified fragment length polymorphism (cDNA-AFLP) in the genic male sterile A and fertile B line of Chinese cabbage pak-choi. Following amplification of 125 pairs of primer combinations, 11 differential fragments were obtained, of which eight were from the B line and the other three were from the A line. Of 11 differential fragments, four were verified by Northern hybridization that were expressed preferentially in fertile flower buds. Results of GenBank BLAST showed that one fragment was with unknown function, whereas the other fragments have strong nucleotide sequence similarities with the polygalacturonase (PG) gene, the pectinesterase (PE) gene, and the polygalacturonase inhibitory protein (PGIP4) gene. Only full-length cDNA from the differential fragment BcMF-A18T16-1 was amplified by rapid amplification of cDNA ends (RACE) and Northern analysis showed that this fragment was expressed only in medium and large-sized flower buds of the B line. The full-length cDNA, designated as BcMF2 (Brassica campestris Male Fertile 2), was 1 485 bp long and was composed of a 1 263-bp open reading frame, which had 83% nucleotide similarity to a PG gene from Arabidopsis encoding polygalacturonase. Analysis of the basic structure of the protein revealed that it had one polygalacturonase active site (RVTCGPGHGLSVGS) at 256th site of amino acids and was classified as being a member of family 28 of the glycosyl hydrolases. The role of the BcMF2 gene on microspore development is discussed in the present paper.
