Abstract
Plant seedling development is capable of following 1 of 2 distinct morphogenic pathways: skotomorphogenesis in darkness and photomorphogenesis in light. Dark-grown Arabidopsis seedlings with recessive mutations at the constitutively photomorphogenic (COP1) locus indicate that the wild-type COP1 protein represses photomorphogenesis in darkness and that light reverses this repressive activity. Using a T-DNA-tagged mutant, we have cloned the COP1 locus. The amino-terminal half of the encoded protein contains a conserved zinc-binding motif, whereas the carboxylterminal half contains a domain homologous to the WD-40 repeat motif of Gβ proteins. The presence of both a putative DNA-binding motif and a G protein-related domain in a single polypeptide suggests that COP1 may be the first of a new class of regulatory molecules. This novel structure could endow COP1 with the capacity to function as a negative transcriptional regulator capable of direct interaction with components of the G protein signaling pathway.
Original language | English (US) |
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Pages (from-to) | 791-801 |
Number of pages | 11 |
Journal | Cell |
Volume | 71 |
Issue number | 5 |
DOIs | |
State | Published - Nov 27 1992 |
Externally published | Yes |
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology