title: Identification of cold-responsive genes in energycane for their use in genetic diversity analysis and future functional marker development.
abstract: Breeding for cold tolerance in sugarcane will allow its cultivation as a dedicated biomass crop in cold environments. Development of functional markers to facilitate marker-assisted breeding requires identification of cold stress tolerance genes. Using suppression subtractive hybridization, 465 cold-responsive genes were isolated from the cold-tolerant energycane Ho02-144. Predicted gene interactions network indicated several associated pathways that may coordinately regulate cold tolerance responses in energycane. Expression analysis of a select set of genes, representing signaling and transcription factors, genes involved in polyamine and antioxidant biosynthesis, protein degradation and in the repair of damaged proteins in the cytosol, showed their time-dependent regulation under cold-stress. Comparative expression profiles of these genes between Ho02-144 and a cold-sensitive clone (L79-1002) showed that almost all genes were induced immediately upon imposition of cold stress and maintained their expression in Ho02-144 whereas they were either downregulated or their upregulation was very low in L79-1002. Simple sequence repeat markers derived from 260 cold-responsive genes showed allelic diversity among the cold-sensitive commercial hybrids that were distinct from the Saccharum spontaneum clones. Future efforts will target sequence polymorphism information of these genes in our ongoing QTL and association mapping studies to identify functional markers associated with cold tolerance in sugar/energycane.
authors.affiliation: School of Plant, Environmental, and Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, United States.
authors.forename: Nisar Ahmad
authors.initials: NA
authors.lastname: Khan
authors.forename: Renesh
authors.initials: R
authors.lastname: Bedre
authors.forename: Arnold
authors.initials: A
authors.lastname: Parco
authors.forename: Lina
authors.initials: L
authors.lastname: Bernaola
authors.forename: Anna
authors.initials: A
authors.lastname: Hale
authors.forename: Collins
authors.initials: C
authors.lastname: Kimbeng
authors.forename: Michael
authors.initials: M
authors.lastname: Pontif
authors.forename: Niranjan
authors.initials: N
authors.lastname: Baisakh
mesh_terms: D016000:Cluster Analysis; D003080:Cold Temperature; D019295:Computational Biology; D018076:DNA, Complementary / Q000235:genetics; D020224:Expressed Sequence Tags; D020869:Gene Expression Profiling; D005819:Genetic Markers; D014644:Genetic Variation; D006824:Hybridization, Genetic; D018895:Microsatellite Repeats / Q000235:genetics*; D058977:Molecular Sequence Annotation; D018515:Plant Leaves / Q000235:genetics / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics; D031786:Saccharum / Q000235:genetics* / Q000502:physiology; D015398:Signal Transduction; D013997:Time Factors; D015533:Transcriptional Activation
chemical_list: D018076:DNA, Complementary; D005819:Genetic Markers; D010940:Plant Proteins; D018749:RNA, Plant
keywords: Cold tolerance; Energycane; Gene expression; Genetic diversity; Sugarcane; eSSR