Campus Units

Horticulture, Botany, Molecular, Cellular and Developmental Biology, Genetics and Genomics

Document Type

Article

Publication Version

Published Version

Publication Date

5-2003

Journal or Book Title

Plant Physiology

Volume

132

Issue

1

First Page

106

Last Page

117

DOI

10.1104/pp.102.015560

Abstract

Potato (Solanum tuberosum) homeobox 1 (POTH1) is a class I homeobox gene isolated from an early-stage tuber cDNA library. The RNA expression pattern ofPOTH1, unlike that of most other class Iknotted-like homeobox genes, is widespread in the cells of both indeterminate and differentiated tissues. Using in situ hybridization, POTH1 transcripts were detected in meristematic cells, leaf primordia, and the vascular procambium of the young stem. Overexpression of POTH1produced dwarf plants with altered leaf morphology. Leaves were reduced in size and displayed a “mouse-ear” phenotype. The mid-vein was less prominent, resulting in a palmate venation pattern. The overall plant height of overexpression lines was reduced due to a decrease in internode length. Levels of intermediates in the gibberellin (GA) biosynthetic pathway were altered, and the bioactive GA, GA1, was reduced by one-half in sense mutants. Accumulation of mRNA for GA 20-oxidase1, a key biosynthetic enzyme, decreased in overexpression lines. In vitro tuberization was enhanced under both short- and long-day photoperiods in several POTH1 overexpression lines. Sense lines produced more tubers at a faster rate than controls. These results imply that POTH1 mediates the development of potato by acting as a negative regulator of GA biosynthesis.

Comments

This article is published as Rosin, Faye M., Jennifer K. Hart, Harry T. Horner, Peter J. Davies, and David J. Hannapel. "Overexpression of a knotted-like homeobox gene of potato alters vegetative development by decreasing gibberellin accumulation." Plant Physiology132, no. 1 (2003): 106-117. doi: 10.1104/pp.102.015560. Copyright American Society of Plant Biologists. Posted wtih permission.

Copyright Owner

American Society of Plant Biologists

Language

en

File Format

application/pdf

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