New insights into Xenopus sex chromosome genomics from the Marsabit clawed frog X. borealis.

In many groups, sex chromosomes change frequently but the drivers of their rapid evolution are varied and often poorly characterized. With an aim of further understanding sex chromosome turnover, we investigated the polymorphic sex chromosomes of the Marsabit clawed frog, Xenopus borealis, using genomic data and a new chromosome-scale genome assembly. We confirmed previous findings that 54.

Genomic and small RNA sequencing of Miscanthus x giganteus shows the utility of sorghum as a reference genome sequence for Andropogoneae grasses.

Background: Miscanthus x giganteus (Mxg) is a perennial grass that produces superior biomass yields in temperate environments. The essentially uncharacterized triploid genome (3n = 57, x = 19) of Mxg is likely critical for the rapid growth of this vegetatively propagated interspecific hybrid.

Results: A survey of the complex Mxg genome was conducted using 454 pyrosequencing of genomic DNA and Illumina sequencing-by-synthesis of small RNA.

Sequence and genetic map of Meloidogyne hapla: A compact nematode genome for plant parasitism.

We have established Meloidogyne hapla as a tractable model plant-parasitic nematode amenable to forward and reverse genetics, and we present a complete genome sequence. At 54 Mbp, M. hapla represents not only the smallest nematode genome yet completed, but also the smallest metazoan, and defines a platform to elucidate mechanisms of parasitism by what is the largest uncontrolled group of plant pathogens worldwide.

A saturation screen for cis-acting regulatory DNA in the Hox genes of Ciona intestinalis.

A screen for the systematic identification of cis-regulatory elements within large (>100 kb) genomic domains containing Hox genes was performed by using the basal chordate Ciona intestinalis. Randomly generated DNA fragments from bacterial artificial chromosomes containing two clusters of Hox genes were inserted into a vector upstream of a minimal promoter and lacZ reporter gene. A total of 222 resultant fusion genes were separately electroporated into fertilized eggs, and their regulatory activities were monitored in larvae.