RESUMEN
The P-element-induced wimpy testis (Piwi) gene is involved in germline stem cell self-renewal, meiosis, RNA silencing, and transcriptional regulation. Piwi genes are relatively well conserved in many species, but their function in poultry species is unclear. In this study, Piwi genes were sequenced using a target-sequence capture assay in quail and 28 breeds of chicken. Single nucleotide polymorphisms (SNPs) and evolutionary aspects of these chicken breeds were then analyzed. We found that SNP sites existed mainly in the introns of a few chicken breeds, and we selected an SNP on intron 4 for further verification by Sanger sequencing, the results of which were similar to those obtained by the target-capture sequencing assay. The evolutionary analysis revealed that there were more mutations in the Chahua and Leghorn breeds than in the other breeds, and that the phylogenetic tree was divided into four main categories that suggested that Piwi is evolutionarily conserved, and mutations in the introns might be associated with gametogenesis. The screened SNPs can be used as candidate markers for Piwi, and our results provide basic information for the further study of Piwi function in poultry.
Asunto(s)
Proteínas Argonautas/genética , Pollos/genética , Polimorfismo de Nucleótido Simple/genética , Aves de Corral/genética , Animales , Cruzamiento , Evolución Molecular , Regulación de la Expresión Génica , Intrones , Filogenia , Interferencia de ARNRESUMEN
Expressed sequence tag (EST)-derived simple sequence repeat (SSR) markers could enrich the current resource of molecular markers. In this study, microsatellite markers were developed for Dendrobium nobile Lindl. by mining the ESTs. Twenty-eight EST-SSRs amplified 2 to 6 nucleotide repeats with a mean number of 2.82 alleles per locus. The observed and expected heterozygosities per locus ranged from 0.158 to 0.579 and 0.422 to 0.752, respectively. These novel EST-SSRs enriched the current resource of molecular markers for the Dendrobium genus and would facilitate further applications in germplasm appraisal, evolution and genetic diversity studies, genetic mapping, and plant breeding of D. nobile and other congeneric species.
Asunto(s)
Dendrobium/genética , Etiquetas de Secuencia Expresada , Repeticiones de Microsatélite , ADN de Plantas/genética , Dendrobium/clasificación , Marcadores Genéticos , Genoma de PlantaRESUMEN
Dendrobium officinale is an endangered orchid from southeast Asia that is known for its medicinal properties in traditional Chinese medicine. We constructed an integrated genetic linkage map of an F(1) population derived from an interspecific cross between D. officinale and D. aduncum (both, 2n = 38), using expressed sequence tag-simple sequence repeats (EST-SSR) and sequence-related amplified polymorphism (SRAP). A total of 349 polymorphic loci, including 261 SRAP loci and 88 EST-SSR loci, were identified for genetic linkage analysis. The software JoinMap 4.0 was used to construct the genetic maps. A total of 157 loci were arranged into 27 major linkage groups, each containing a minimum of four markers, and a further 23 markers were distributed to five triplets and four doublets, the frame map covered a total distance of 1580.4 cM, with a mean of 11.89 cM between adjacent markers. This primary map of the D. officinale and D. aduncum hybrid provides a basis for genetic studies and should facilitate future studies of medical traits mapping and marker-assisted selection in Dendrobium species breeding programs.