caa a22 4500 467893470 CHVBK 20180406152755.0 cr unu---uuuuu 170328e20060101xx s 000 0 eng 10.1007/s11103-005-2226-y doi (NATIONALLICENCE)springer-10.1007/s11103-005-2226-y Dirigent Proteins in Conifer Defense: Gene Discovery, Phylogeny, and Differential Wound- and Insect-induced Expression of a Family of DIR and DIR-like Genes in Spruce ( Picea spp.) [Elektronische Daten] [Steven Ralph, Ji-Young Park, Jörg Bohlmann, Shawn Mansfield] The outer stem tissues of conifers provide a durable constitutive and inducible defense barrier consisting of suberized or lignified periderm, sclereids, a network of terpenoid-filled resin ducts, and phenolic phloem parenchyma cells. Microarray gene expression profiling of Sitka spruce (Picea sitchensis) bark attacked by stem-boring weevils (Pissodes strobi) or through mechanical wounding demonstrated significant accumulation of transcripts resembling dirigent protein (DIR) genes. To investigate this gene family and its spatial and temporal patterns of expression in conifer defense, we isolated cDNAs representing 19 unique DIR and DIR-like genes from Sitka spruce, white spruce (P. glauca), and interior spruce (P. glauca× engelmannii). Sequence alignments also identified a large number of DIR-like proteins in other plant species, which share several conserved protein motifs with known DIR proteins. Phylogenetic analysis of 72 DIR and DIR-like proteins suggests five distinct subfamilies, DIR-a and four DIR-like subfamilies (DIR-b, DIR-c, DIR-d and DIR-e). Previously characterized members of the DIR-a subfamily direct stereoselective phenolic coupling reactions in the formation of lignans and possibly lignins. The spruce genes identified here are members of the DIR-a and DIR-b subfamilies. Using gene-specific quantitative real-time PCR we measured constitutive expression for six DIR-a genes and three DIR-like genes in different stem tissues, green shoot tips, and roots of Sitka spruce. DIR-like genes revealed ubiquitous high expression in all tissues. In contrast, the six DIR-a genes showed a gradient of transcript abundance in stem tissues with highest levels in the outer cortex and lowest levels in the inner xylem. Gene-specific transcript profiling of six DIR-a genes confirmed rapid and strong accumulation (up to 500-fold) in wound- and weevil-induced stem bark and xylem. These findings suggest a role for spruce DIR genes in constitutive and induced phenolic defense mechanisms against stem-boring insects. Springer, 2006 conifer genomics nationallicence gymnosperm nationallicence lignan and lignin formation nationallicence Pissodes strobi nationallicence plant herbivore defense nationallicence plant-insect interactions nationallicence DIR : dirigent nationallicence EST : expressed sequence tag nationallicence ORF : open reading frame nationallicence PAL : phenylalanine ammonia lyase nationallicence PP cells : phloem parenchyma cells nationallicence Ralph Steven Michael Smith Laboratories, University of British Columbiad, V6T1Z4, Vancouver, BC, Canada aut Park Ji-Young Department of Wood Science, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, V6T1Z4, Vancouver, BC, Canada aut Bohlmann Jörg Michael Smith Laboratories, University of British Columbiad, V6T1Z4, Vancouver, BC, Canada aut Mansfield Shawn Department of Wood Science, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, V6T1Z4, Vancouver, BC, Canada aut Plant Molecular Biology Kluwer Academic Publishers 60/1(2006-01-01), 21-40 0167-4412 60:1<21 2006 60 11103 https://doi.org/10.1007/s11103-005-2226-y text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11103-005-2226-y text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ralph Steven Michael Smith Laboratories, University of British Columbiad, V6T1Z4, Vancouver, BC, Canada aut NATIONALLICENCE 700 1- Park Ji-Young Department of Wood Science, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, V6T1Z4, Vancouver, BC, Canada aut NATIONALLICENCE 700 1- Bohlmann Jörg Michael Smith Laboratories, University of British Columbiad, V6T1Z4, Vancouver, BC, Canada aut NATIONALLICENCE 700 1- Mansfield Shawn Department of Wood Science, University of British Columbia, Forest Sciences Centre, 2424 Main Mall, V6T1Z4, Vancouver, BC, Canada aut NATIONALLICENCE 773 0- Plant Molecular Biology Kluwer Academic Publishers 60/1(2006-01-01), 21-40 0167-4412 60:1<21 2006 60 11103 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer