title: SHORT INTERNODES-like genes regulate shoot growth and xylem proliferation in Populus.
abstract: • Genes controlling plant growth and form are of considerable interest, because they affect survival and productivity traits, and are largely unknown or poorly characterized. The SHORT INTERNODES(SHI) gene is one of a 10-member SHI-RELATED SEQUENCE (SRS) gene family in Arabidopsis that includes important developmental regulators. • Using comparative sequence analysis of the SRS gene families in poplar and Arabidopsis, we identified two poplar proteins that are most similar to SHI and its closely related gene STYLISH1 (STY1). The two poplar genes are very similar in sequence and expression and are therefore probably paralogs with redundant functions. • RNAi suppression of the two Populus genes enhanced shoot and root growth, whereas the overexpression of Arabidopsis SHI in poplar reduced internode and petiole length. The suppression of the two genes increased fiber length and the proportion of xylem tissue, mainly through increased xylem cell proliferation. The transgenic modifications were also associated with significant changes in the concentrations of gibberellins and cytokinin. • We conclude that Populus SHI-RELATED SEQUENCE (SRS) genes play an important role in the regulation of vegetative growth, including wood formation, and thus could be useful tools for the modification of biomass productivity, wood quality or plant form.
authors.affiliation: School of Forest Research and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Zawaski
authors.affiliation: Department of Cell and Molecular Physiology, University of North Carolina, Chapel Hill, NC 27599, USA.
authors.forename: Mahita
authors.initials: M
authors.lastname: Kadmiel
authors.affiliation: Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331-5752, USA.
authors.forename: Cathleen
authors.initials: C
authors.lastname: Ma
authors.affiliation: National Engineering Laboratory for Tree Breeding, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of Forestry Administration of China, College of Life Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Gai
authors.affiliation: National Engineering Laboratory for Tree Breeding, The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of Forestry Administration of China, College of Life Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Xiangning
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331-5752, USA.
authors.forename: Steve H
authors.initials: SH
authors.lastname: Strauss
authors.affiliation: School of Forest Research and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931, USA.
authors.forename: Victor B
authors.initials: VB
authors.lastname: Busov
mesh_terms: D018533:Biomass; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D010641:Phenotype; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000378:metabolism; D018515:Plant Leaves / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000033:anatomy & histology / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000033:anatomy & histology / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D032107:Populus / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D034622:RNA Interference; D012333:RNA, Messenger / Q000235:genetics; D018749:RNA, Plant / Q000235:genetics; D017422:Sequence Analysis, DNA; D013997:Time Factors; D014934:Wood / Q000254:growth & development; D052584:Xylem / Q000254:growth & development* / Q000378:metabolism
chemical_list: D010937:Plant Growth Regulators; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant