RT Journal Article
SR Electronic
T1 Involvement of an ABC Transporter in a Developmental Pathway Regulating Hypocotyl Cell Elongation in the Light
JF The Plant Cell
JO Plant Cell
FD American Society of Plant Biologists
SP 1623
OP 1636
DO 10.1105/tpc.10.10.1623
VO 10
IS 10
A1 Sidler, Michael
A1 Hassa, Paul
A1 Hasan, Sameez
A1 Ringli, Christoph
A1 Dudler, Robert
YR 1998
UL http://www.plantcell.org/content/10/10/1623.abstract
AB In the dark, plant seedlings follow the skotomorphogenetic developmental program, which results in hypocotyl cell elongation. When the seedlings are exposed to light, a switch to photomorphogenetic development occurs, and hypocotyl cell elongation is inhibited. We have manipulated the expression of the AtPGP1 (for Arabidopsis thaliana P glycoprotein1) gene in transgenic Arabidopsis plants by using sense and antisense constructs. We show that within a certain light fluence rate window, overexpression of the AtPGP1 gene under the control of the cauliflower mosaic virus 35S promoter causes plants to develop longer hypocotyls, whereas expression of the gene in antisense orientation results in hypocotyls shorter than those occurring in the wild type. In the dark, hypocotyls of transgenic and wild-type plants are indistinguishable. Because the AtPGP1 gene encodes a member of the superfamily of ATP binding cassette–containing (ABC) transporters, these results imply that a transport process is involved in a hypocotyl cell elongation pathway active in the light. The AtPGP1 transporter is localized in the plasmalemma, as indicated by immunohistochemical techniques and biochemical membrane separation methods. Analysis of the AtPGP1 expression pattern by using reporter gene constructs and in situ hybridization shows that in wild-type seedlings, AtPGP1 is expressed in both the root and shoot apices.