Assembly of Aegilops comosa chromosomes

We sequenced and assembled seven chromosomes of Aegilops comosa. The
assembly with Meraculous resulted in ~ 50k - 186k scaffolds per chromosome
with N50 size 6.4kb - 20.2kb. The scaffold sequences were used for
development of molecular markers specific for cDNAs sequences mapped on
Ae. comosa chromosomes Pairwise alignment of wheat cDNA-sequences and the
chromosomal scaffolds of Ae. comosa identified candidate sequences. In
order to analyze the structure and homeology of Aegilops chromosomes,
forty-three mapped wheat cDNAs covering all seven chromosome groups were
localized by FISH.

本研究对顶芒山羊草（Aegilops comosa）的7条染色体完成了测序与组装。使用Meraculous软件进行组装后，每条染色体可获得约50k~186k个支架序列（scaffold），其N50长度介于6.4kb至20.2kb之间。所得支架序列被用于开发针对定位在顶芒山羊草染色体上的互补DNA（complementary DNA, cDNA）序列的特异性分子标记。通过对小麦互补DNA序列与顶芒山羊草染色体支架序列进行双序列比对，筛选得到候选序列。为分析山羊草属（Aegilops）染色体的结构与部分同源性，研究人员通过荧光原位杂交（fluorescence in situ hybridization, FISH）技术，对覆盖全部7个染色体组的43个已定位小麦互补DNA序列完成了定位。