title: An agravitropic mutant of Arabidopsis, endodermal-amyloplast less 1, that lacks amyloplasts in hypocotyl endodermal cell layer.
abstract: We have isolated a new recessive mutant of Arabidopsis thaliana for gravitropism, endodermal-amyloplast less 1 (eal1). eal1 shows reduced gravitropism in hypocotyl, and completely lacks gravitropism in inflorescence stems; root gravitropism is not affected. Starch staining with I-KI solution reveals almost no amyloplasts in eal1 hypocotyls when grown on a sucrose-free medium, though the root columella cells contain as many amyloplasts as wild type. On a medium containing 1% sucrose, eal1 hypocotyls contain as many starch granules as those of wild type, suggesting that starch synthesis is not affected in eal1. The endodermal cell layer which is thought to function as statocytes in hypocotyls is present in eal1. These results suggest that differentiation or development of gravity-responsive amyloplasts are affected in eal1 hypocotyls.
authors.affiliation: Division of Biological Science, Graduate School of Environmental Earth Science, Hokkaido University, Sapporo, 060-0810 Japan.
authors.forename: K
authors.initials: K
authors.lastname: Fujihira
authors.forename: T
authors.initials: T
authors.lastname: Kurata
authors.forename: M K
authors.initials: MK
authors.lastname: Watahiki
authors.forename: I
authors.initials: I
authors.lastname: Karahara
authors.forename: K T
authors.initials: KT
authors.lastname: Yamamoto
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins; D018522:Gravitropism / Q000235:genetics; D018546:Hypocotyl / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation; D063245:Plant Development; D018547:Plant Stems / Q000235:genetics / Q000254:growth & development; D010944:Plants / Q000235:genetics; D013213:Starch / Q000096:biosynthesis*
chemical_list: D029681:Arabidopsis Proteins; D008565:Membrane Proteins; C116681:agravitropic protein, Arabidopsis; D013213:Starch