title: Development of 23 novel polymorphic EST-SSR markers for the endangered relict conifer Metasequoia glyptostroboides.
abstract: OBJECTIVE
  Metasequoia glyptostroboides is an endangered relict conifer species endemic to China. In this study, expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed using transcriptome mining for future genetic and functional studies.
  
  
  RESULTS
  We collected 97,565 unigene sequences generated by 454 pyrosequencing. A bioinformatics analysis identified 2087 unique and putative microsatellites, from which 96 novel microsatellite markers were developed. Fifty-three of the 96 primer sets successfully amplified clear fragments of the expected sizes; 23 of those loci were polymorphic. The number of alleles per locus ranged from two to eight, with an average of three, and the observed and expected heterozygosity values ranged from 0 to 1.0 and 0.117 to 0.813, respectively.
  
  
  CONCLUSIONS
  These microsatellite loci will enrich the genetic resources to develop functional studies and conservation strategies for this endangered relict species.
authors.affiliation: National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Jin
authors.affiliation: School of Nature Conservation, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Quanxin
authors.initials: Q
authors.lastname: Bi
authors.affiliation: School of Nature Conservation, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Wenbin
authors.initials: W
authors.lastname: Guan
authors.affiliation: National Engineering Laboratory for Tree Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China.
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Mao
keywords: 454 pyrosequencing; Cupressaceae; EST-SSR; Metasequoia glyptostroboides; microsatellite; relict plant