Kaur Parminder, Larson Steven R, Shaun Bushman B, Wang Richard R-C, Mott Ivan W, Hole David, Thimmapuram Jyothi, Gong George, Liu Lei
Plants, Soils, and Climate Department, Utah State University, Logan, UT, 84322-4800, USA.
Funct Integr Genomics. 2008 Nov;8(4):375-86. doi: 10.1007/s10142-008-0085-8. Epub 2008 Jun 10.
Leymus cinereus and L. triticoides are large caespitose and rhizomatous perennial grasses, respectively. Previous studies detected quantitative trait loci (QTL) controlling rhizome spreading near the viviparous1 (vp1) gene markers on linkage groups LG3a and LG3b in two families, TTC1 and TTC2, derived from Leymus triticoides x Leymus cinereus hybrids. The wheat tiller inhibition gene (tin3) is located on Triticum monococcum chromosome 3 A(m)L near vp1. Triticeae group 3 is reportedly collinear with rice chromosome 1, which also contains the maize barren stalk1 and rice lax branching orthogene near vp1. However, previous studies lacked cross-species markers for comparative mapping and showed possible rearrangements of Leymus group 3 in wheat-Leymus racemosus chromosome addition lines. Here, we developed expressed sequence tag (EST) markers from Leymus tiller and rhizomes and mapped sequences aligned to rice chromosome 1. Thirty-eight of 44 informative markers detected loci on Leymus LG3a and LG3b that were collinear with homoeologous sequences on rice chromosome 1 and syntenous in homoeologous group 3 wheat-Leymus and wheat-Thinopyrum addition lines. A SCARECROW-like GRAS-family transcription factor candidate gene was identified in the Leymus EST library, which aligns to the Leymus chromosome group 3 growth habit QTL and a 324-kb rice chromosome 1 region thought to contain the wheat tin3 gene.
羊草和小麦状赖草分别是大型丛生且具根状茎的多年生草本植物。先前的研究在源自小麦状赖草×羊草杂交种的两个家系TTC1和TTC2中，在连锁群LG3a和LG3b上靠近胎萌1（vp1）基因标记的位置检测到了控制根状茎蔓延的数量性状基因座（QTL）。小麦分蘖抑制基因（tin3）位于一粒小麦3A(m)L染色体上靠近vp1的位置。据报道，小麦族第3组与水稻第1染色体共线，该染色体在vp1附近还包含玉米无穗轴1和水稻松散分枝的直系同源基因。然而，先前的研究缺乏用于比较作图的跨物种标记，并显示在小麦-总状花序赖草染色体附加系中羊草第3组可能存在重排。在此，我们从小麦状赖草的分蘖和根状茎中开发了表达序列标签（EST）标记，并对与水稻第1染色体比对的序列进行了定位。44个信息性标记中的38个在羊草LG3a和LG3b上检测到了与水稻第1染色体上的同源序列共线且在小麦-羊草和小麦-披碱草同源群3附加系中同源的位点。在羊草EST文库中鉴定出一个类似稻草人（SCARECROW）的GRAS家族转录因子候选基因，它与羊草染色体组3生长习性QTL以及一个被认为包含小麦tin3基因的324-kb水稻第1染色体区域比对。
