title: Small heat shock proteins can release light dependence of tobacco seed during germination.
abstract: Small heat shock proteins (sHSPs) function as ATP-independent molecular chaperones, and although the production and function of sHSPs have often been described under heat stress, the expression and function of sHSPs in fundamental developmental processes, such as pollen and seed development, have also been confirmed. Seed germination involves the breaking of dormancy and the resumption of embryo growth that accompany global changes in transcription, translation, and metabolism. In many plants, germination is triggered simply by imbibition of water; however, different seeds require different conditions in addition to water. For small-seeded plants, like Arabidopsis (Arabidopsis thaliana), lettuce (Lactuca sativa), tomato (Solanum lycopersicum), and tobacco (Nicotiana tabacum), light is an important regulator of seed germination. The facts that sHSPs accumulate during seed development, sHSPs interact with various client proteins, and seed germination accompanies synthesis and/or activation of diverse proteins led us to investigate the role of sHSPs in seed germination, especially in the context of light dependence. In this study, we have built transgenic tobacco plants that ectopically express sHSP, and the effect was germination of the seeds in the dark. Administering heat shock to the seeds also resulted in the alleviation of light dependence during seed germination. Subcellular localization of ectopically expressed sHSP was mainly observed in the cytoplasm, whereas heat shock-induced sHSPs were transported to the nucleus. We hypothesize that ectopically expressed sHSPs in the cytoplasm led the status of cytoplasmic proteins involved in seed germination to function during germination without additional stimulus and that heat shock can be another signal that induces seed germination.
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Hyun Jo
authors.initials: HJ
authors.lastname: Koo
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Soo Min
authors.initials: SM
authors.lastname: Park
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Keun Pill
authors.initials: KP
authors.lastname: Kim
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Mi Chung
authors.initials: MC
authors.lastname: Suh
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Mi Ok
authors.initials: MO
authors.lastname: Lee
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Seong-Kon
authors.initials: SK
authors.lastname: Lee
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.).
authors.forename: Xia
authors.initials: X
authors.lastname: Xinli
authors.affiliation: School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151-742, Korea (H.J.K., S.M.P., K.P.K., M.C.S., M.O.L., S.-K.L., C.B.H.); andCollege of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, People's Republic of China (X.X.) hcb@snu.ac.kr.
authors.forename: Choo Bong
authors.identifier: http://orcid.org/0000-0001-7753-1502
authors.initials: CB
authors.lastname: Hong
mesh_terms: D003624:Darkness; D018525:Germination / Q000528:radiation effects*; D050888:Heat-Shock Proteins, Small / Q000378:metabolism*; D018869:Heat-Shock Response / Q000528:radiation effects; D008027:Light; D010940:Plant Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified; D021381:Protein Transport; D012639:Seeds / Q000254:growth & development* / Q000528:radiation effects* / Q000648:ultrastructure; D013347:Subcellular Fractions / Q000378:metabolism; D013997:Time Factors; D014026:Nicotiana / Q000254:growth & development* / Q000528:radiation effects* / Q000648:ultrastructure
chemical_list: D050888:Heat-Shock Proteins, Small; D010940:Plant Proteins