ζ （zeta）-carotene desaturase （ZDS） is a key enzyme for carotenoid biosynthesis, demonstrating high association with the yellow pigment （YP） content in wheat grain. Cloning ZDS gene and developing functional mar...ζ （zeta）-carotene desaturase （ZDS） is a key enzyme for carotenoid biosynthesis, demonstrating high association with the yellow pigment （YP） content in wheat grain. Cloning ZDS gene and developing functional markers are important for marker-assisted selection in wheat breeding. In the present study, the full-length DNA sequence of a ZDS gene on wheat chromosome 2A, designated TaZds-A1, was cloned, with 14 exons and 13 introns, and it has an open reading frame （ORF） of 1 707 bp, encoding 568 amino acid residues. A co-dominant functional marker, YP2A-1, was designed based on the polymorphisms of two alleles at the locus, TaZds-Ala and TaZds-Alb, yielding 183- and 179-bp fragments in TaZds-Ala and TaZds-Alb genotypes, respectively. A new QTL for YP content was detected on chromosome 2A, co-segregating with the functional marker YP2A-1 and TaZds-A1; it explained 11.3% of the phenotypic variance for YP content in a doubled haploid （DH） population from Zhongyou 9507/CA9632. Among 217 Chinese wheat cultivars and advanced lines, the average grain YP content of 126 cultivars with TaZds-Alb allele was 7.8% higher than that of 91 cultivars with TaZds- Ala allele.展开更多
ζ-Carotene desaturase(ZDS)is an important enzyme in carotenoid biosynthesis.Here,the Brassica oleracea var.alboglabra ZDS(Boa ZDS)gene was cloned from Chinese kale via reverse transcription-polymerase chain reaction(...ζ-Carotene desaturase(ZDS)is an important enzyme in carotenoid biosynthesis.Here,the Brassica oleracea var.alboglabra ZDS(Boa ZDS)gene was cloned from Chinese kale via reverse transcription-polymerase chain reaction(RT-PCR)and deposited in Gen Bank(accession number KY662297).The Boa ZDS gene contains an open reading frame of 1 686 bp that encodes a 561-amino acid protein.Sequence analysis indicates that the ZDS protein is apparently conserved during plant evolution and is most closely related to B.oleracea var.capitata and B.rapa.The promoter sequence of the Boa ZDS gene was predicted to harbor several cis-acting elements that are related to light and phytohormone responses.Semiquantitative RT-PCR analysis showed that Boa ZDS expression varied among different developmental stages and organs.Relative ZDS expression remained stable during germination and seedling stages and rapidly increased at the mature leaf stage.The leaves showed the highest ZDS expression levels compared to the other organs.ZDS expression decreased in all flower tissues during blooming.The fused protein of Boa ZDS was obtained by prokaryotic expression.Heterologous expression of Boa ZDS in Escherichia coli confirmed that Boa ZDS encodes a functionalζ-carotene desaturase that increases β-carotene accumulation in E.coli cells harboring a β-carotene-producing plasmid.The findings of the present study provide a molecular basis for the elucidation of ZDS gene function in Chinese kale.展开更多
基金supported by the National Natural Science Foundation of China (30871522 and 30830072)the National Basic Research Program of China(2009CB118300)an Earmarked Fund for the Modern Agro-Industry Technology Research System, China (CARS-3-1-3)
文摘ζ （zeta）-carotene desaturase （ZDS） is a key enzyme for carotenoid biosynthesis, demonstrating high association with the yellow pigment （YP） content in wheat grain. Cloning ZDS gene and developing functional markers are important for marker-assisted selection in wheat breeding. In the present study, the full-length DNA sequence of a ZDS gene on wheat chromosome 2A, designated TaZds-A1, was cloned, with 14 exons and 13 introns, and it has an open reading frame （ORF） of 1 707 bp, encoding 568 amino acid residues. A co-dominant functional marker, YP2A-1, was designed based on the polymorphisms of two alleles at the locus, TaZds-Ala and TaZds-Alb, yielding 183- and 179-bp fragments in TaZds-Ala and TaZds-Alb genotypes, respectively. A new QTL for YP content was detected on chromosome 2A, co-segregating with the functional marker YP2A-1 and TaZds-A1; it explained 11.3% of the phenotypic variance for YP content in a doubled haploid （DH） population from Zhongyou 9507/CA9632. Among 217 Chinese wheat cultivars and advanced lines, the average grain YP content of 126 cultivars with TaZds-Alb allele was 7.8% higher than that of 91 cultivars with TaZds- Ala allele.
基金supported by National Natural Science Foundation of China(31500247)Key Project of Department of Education of Sichuan Province(14ZA0016)Natural Science Foundation of Zhejiang Province(LZ15C150001)
文摘ζ-Carotene desaturase(ZDS)is an important enzyme in carotenoid biosynthesis.Here,the Brassica oleracea var.alboglabra ZDS(Boa ZDS)gene was cloned from Chinese kale via reverse transcription-polymerase chain reaction(RT-PCR)and deposited in Gen Bank(accession number KY662297).The Boa ZDS gene contains an open reading frame of 1 686 bp that encodes a 561-amino acid protein.Sequence analysis indicates that the ZDS protein is apparently conserved during plant evolution and is most closely related to B.oleracea var.capitata and B.rapa.The promoter sequence of the Boa ZDS gene was predicted to harbor several cis-acting elements that are related to light and phytohormone responses.Semiquantitative RT-PCR analysis showed that Boa ZDS expression varied among different developmental stages and organs.Relative ZDS expression remained stable during germination and seedling stages and rapidly increased at the mature leaf stage.The leaves showed the highest ZDS expression levels compared to the other organs.ZDS expression decreased in all flower tissues during blooming.The fused protein of Boa ZDS was obtained by prokaryotic expression.Heterologous expression of Boa ZDS in Escherichia coli confirmed that Boa ZDS encodes a functionalζ-carotene desaturase that increases β-carotene accumulation in E.coli cells harboring a β-carotene-producing plasmid.The findings of the present study provide a molecular basis for the elucidation of ZDS gene function in Chinese kale.
