Genyi Li

Gene for gene alignment between the Brassica and Arabidopsis genomes by direct transcriptome mapping.

We report a global gene for gene alignment of the genomes of Brassica oleracea and Arabidopsis thaliana by construction of a transcriptome map based on B. oleracea cDNAs obtained from leaf tissue. cDNAs were synthesized from total RNA extracted from individual F2s of a mapping population resulting from crossing double-haploids of broccoli and cauliflower. The map consisted of 247 cDNA markers obtained by the SRAP technique. After sequencing 190 of the polymorphic cDNA bands, FASTA detected 169 sequences with similarity to genes reported in Arabidopsis. There was extensive colinearity between the two genomes for chromosomal segments rather than for whole chromosomes, often showing inversions and deletions/insertions. Large-scale duplications were observed in the B. oleracea genome, but were unevenly distributed, arguing against ancient triplication of the entire genome. The most duplicated segments corresponded to those found on Arabidopsis chromosomes 1 and 5, whereas chromosomes 2 and 4 were the least represented in Brassica. Clear differences in the similarity score value of related sequences allowed the identification of orthologs. Transcriptome mapping is an efficient approach that allows gene-for-gene alignment between a fully sequenced and a poorly characterized genome.

Glucosinolate contents in maca (Lepidium peruvianum Chacón) seeds, sprouts, mature plants and several derived commercial products

Several products derived from processed maca hypocotyls (Lepidium peruvianum Chacón, previously known asL. meyenii Walp.) were surveyed for glucosinolate content and quantified by HPLC analysis. These included pills, capsules, flour, liquor, tonic and mayonnaise. Different plant organs such as fresh hypocotyls and leaves, seeds, dry hypocotyls, and sprouts were also included in the survey. The most abundant glucosinolates detected in fresh and dry hypocotyls and leaves were the aromatic glucosinolates, benzylglucosinolate (glucotropaeolin) and p-methoxybenzylglucosinolate. Maca seeds and sprouts differed in profile from hypocotyls and leaves due to the modification of benzylglucosinolate. No glucosinolates were detected in liquor and tonic, while mayonnaise had only trace amounts of those glucosinolates. It had instead allylglucosinolate (sinigrin), which is an aliphatic glucosinolate. The pills, capsules and flour had the same glucosinolates as those observed in hypocotyls, but in variable amounts. The richest sources of glucosinolates were seeds, fresh hypocotyls and sprouts, in that order.ResumenSe determinaron glucosinolatos por HPLC (cromatografía líquida de alto rendimiento) en la maca (Lepidium peruvianum Chacón,antes L. meyenii Walp.) y en varios de sus productos derivados. Estos incluyeron comprimidos, cápsulas, harina, licor, tonico y mayonesa de maca. Además de plántulas, se muestrearon semillas, hojas e hipocotilos frescos, así como hipocotilos secos. Los glucosinolatos más abundantes detectados en hojas y en hipocotilos frescos y secos fueron los aromáticos benzylglucosinolato (glucotropaeolin) y p-methoxybenzylglucosinolato. Las plántulas y semillas mostraron perfiles de glucosinolatos diferentes al de las hojas e hipocotilos debido a la modificación de benzylglucosinolato. No se detectaron glucosinolatos en el licor y tonico, mientras que el contenido de estos en la mayonesa fue mínimo. Esta mas bien mostro el glucosinolato alifático allylglucosinolato (sinigrin). Los comprimidos, cápsulas, y harina mostraron el mismo perfil de glucosinolatos que el de los hipocotilos. En orden de mayor a menor las fuentes más ricas en glucosinolatos fueron las semillas, hipocotilos frescos y plántulas.

Survey of aliphatic glucosinolates in Sicilian wild and cultivated Brassicaceae

In the frame of the activities carried out to exploit Sicilian local cultivars of brassicas, we focused our attention on some of the potential health compounds of various local cruciferous crops. These compounds are of interest to improve the quality of the produce with the aim to develop new cultivars capable of providing functional foods able to prevent disease. In this context, we surveyed for the presence of specific glucosinolates in local cultivars of broccoli, cauliflower, kale, and in some wild species widespread in Sicily, using as control various commercial cultivars. Glucosinolate composition varied extensively among species and crops of the same species, such as cauliflower, broccoli and kale. Cultivar variation for glucosinolate profile was also observed for some crops. For example, Sicilian cultivars of cauliflower possessing colored curds displayed a high content of glucosinolates, glucoraphanin in particular, compared to white curd commercial cultivars. Also some wild species had a high content of other glucosinolates.

SRAP Molecular Marker Technology in Plant Science

Molecular markers are commonly used in genetic diversity analysis, genetic map construc‐ tion, gene mapping and cloning, and marker assisted selection in plant breeding. Based on detection procedure, most molecular marker technologies can be classified into hybridiza‐ tion-based or PCR-based systems. Restriction fragment length polymorphism (RFLP) is the first hybridization-based molecular marker system that was intensively used at the begin‐ ning of the molecular biology era in life science while hybridization-based marker methods such as microarrays and diversity array technology (DArT) are used currently to detect sin‐ gle nucleotide polymorphisms (SNP). In contrast, many PCR-based molecular marker detec‐ tion methods have been developed. For example, amplified fragment length polymorphism (AFLP), random amplified polymorphic DNA (RAPD), simple sequence repeats (SSR) and sequence related amplified polymorphism (SRAP), inter-simple sequence repeat (ISSR), se‐ quence tagged site (STS), and sequence characterized amplification region (SCAR), are com‐ monly used in genomic analysis (Jones et al., 2009).

Structure, sequence, and phylogeny of the members of the Ck1 gene family in Brassica oleracea and Arabidopsis thaliana (Brassicaceae)

Abstract We report on the comparative analysis of the sequences of four and five copies of the Ck1 (caseine kinase-like) gene in Arabidopsis thaliana and Brassica oleracea , respectively. These duplicate genes could be separated into two major groups based on their number of exons. The first group, including most of the genes, contained 14 exons, whereas the second one had 13 exons. Based on this separation as well as on the DNA and amino acid sequence identity and phylogenetic analysis, it was possible to assign orthology and paralogy to these genes and to draw conclusions on their possible evolutionary relationships.