Haploid gynogens facilitate disomic marker development in paleotetraploid sturgeons.

Acipenseriformes (sturgeons and paddlefishes) are of substantial conservation concern, and development of genomic resources for these species is difficult due to past whole genome duplication. Development of disomic markers for polyploid organisms can be challenging due to difficulty in resolving alleles at a single locus from those among duplicated loci. In this study, we detail the development of disomic markers for the endangered pallid sturgeon (Scaphirhynchus albus) found in North America.

Improved genetic identification of acipenseriform embryos with application to the endangered pallid sturgeon Scaphirhynchus albus.

We produced pallid sturgeon Scaphirhynchus albus embryos at five pre-hatch developmental stages and isolated and quantified genomic DNA from four of the stages using four commercial DNA isolation kits. Genomic DNA prepared using the kit that produced the largest yields and concentrations were used for microsatellite DNA analyses of 10-20 embryos at each of the five developmental stages. We attempted to genotype the hatchery-produced embryos at 19 microsatellite loci and confirmed reliable genotyping by comparing the microsatellite genotypes to those of known parents.

Complete mitochondrial genome of the nurse shark .

We determined the complete mitochondrial genome sequence of nurse shark The circular DNA of 16692 bp comprises 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, a non-coding control region and a non-coding origin of light strand replication with typical gene order of vertebrates. The nurse shark formed a well-supported clade that included whale shark and zebra shark within the Orectolobiformes in a phylogenetic tree constructed with other published mitochondrial genomes of sharks.

Genetic heterogeneity in a cyclical forest pest, the southern pine beetle, Dendroctonus frontalis, is differentiated into east and west groups in the southeastern United States.

The southern pine beetle, Dendroctonus frontalis Zimmerman (Coleoptera: Curculionidae) is an economically important pest species throughout the southeastern United States, Arizona, Mexico, and Central America. Previous research identified population structure among widely distant locations, yet failed to detect population structure among national forests in the state of Mississippi. This study uses microsatellite variation throughout the southeastern United States to compare the southern pine beetle's pattern of population structure to phylogeographic patterns in the region, and to provide information about dispersal.

Primordial linkage of β2-microglobulin to the MHC.

β2-Microglobulin (β2M) is believed to have arisen in a basal jawed vertebrate (gnathostome) and is the essential L chain that associates with most MHC class I molecules. It contains a distinctive molecular structure called a constant-1 Ig superfamily domain, which is shared with other adaptive immune molecules including MHC class I and class II. Despite its structural similarity to class I and class II and its conserved function, β2M is encoded outside the MHC in all examined species from bony fish to mammals, but it is assumed to have translocated from its original location within the MHC early in gnathostome evolution.

World phylogeography and male-mediated gene flow in the sandbar shark, Carcharhinus plumbeus.

The sandbar shark, Carcharhinus plumbeus, is a large, cosmopolitan, coastal species. Females are thought to show philopatry to nursery grounds while males potentially migrate long distances, creating an opportunity for male-mediated gene flow that may lead to discordance in patterns revealed by mitochondrial DNA (mtDNA) and nuclear markers. While this dynamic has been investigated in elasmobranchs over small spatial scales, it has not been examined at a global level.

Development of DNA microsatellite markers in the multiband butterflyfish (Chaetodon multicinctus).

Twelve polymorphic microsatellite loci were developed in the multiband (pebbled) butterflyfish Chaetodon multicinctus. The loci were scored in 45 individuals from Hawaii. There were five to 21 alleles per locus with observed heterozygosity ranging from 0.

Fine scale gene flow and individual movements among subpopulations of Centrolene prosoblepon (Anura: Centrolenidae).

Dispersal capabilities determine and maintain local gene flow, and this has implications for population persistence and/or recolonization following environmental perturbations (natural or anthropogenic), disease outbreaks, or other demographic collapses. To predict recolonization and understand dispersal capacity in a stream-breeding frog, we examined individual movement patterns and gene flow among four subpopulations of the Neotropical glassfrog, Centrolene prosoblepon, at a mid-elevation cloud forest site at El Copé, Panama. We measured male movement directly during a two year mark-recapture study, and indirectly with gene flow estimates from mitochondrial DNA sequences (mtDNA).

Fine-scale genetic population structure of southern pine beetle (Coleoptera: Curculionidae) in Mississippi forests.

The southern pine beetle, Dendroctonus frontalis Zimmerman, is the most destructive insect pest of pine forests in the southeastern United States, Mexico, and Central America. Southern pine beetle aggressively attacks pine trees, and when in epidemic stages, they are capable of killing even the most healthy pine trees in a short period of time. Despite the amount of destruction caused by the southern pine beetle and the amount of monetary loss faced by the timber industry and recreation, the population genetics of this species has been limited to comparisons among distant geographic locations.