Arabidopsis CONSTANS-LIKE3 is a positive regulator of red light signaling and root growth.

• CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1) is an E3 ubiquitin ligase that represses photomorphogenesis in the dark. Therefore, proteins interacting with COP1 could be important regulators of light-dependent development. Here, we identify CONSTANS-LIKE3 (COL3) as a novel interaction partner of COP1. A green fluorescent protein-COL3 fusion protein colocalizes with COP1 to nuclear speckles when transiently expressed in plant cells. This localization requires the B-box domains in COL3, indicating a novel function of this domain. A loss-of-function col3 mutant has longer hypocotyls in red light and in short days. Unlike constans, the col3 mutant flowers early and shows a reduced number of lateral branches in short days. The mutant also exhibits reduced formation of lateral roots. The col3 mutation partially suppresses the cop1 and deetiolated1 (det1) mutations in the dark, suggesting that COL3 acts downstream of both of these repressors. However, the col3 mutation exerts opposing effects on cop1 and det1 in terms of lateral roots and anthocyanin accumulation, suggesting that COL3 also has activities that are independent of COP1 and DET1. In conclusion, we have identified COL3 as a positive regulator of photomorphogenesis that acts downstream of COP1 but can promote lateral root development independently of COP1 and also function as a daylength-sensitive regulator of shoot branching.

Ämnesord

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Nyckelord

Amino Acid Sequence

Arabidopsis

anatomy & histology

genetics

physiology

Arabidopsis Proteins

genetics

metabolism

Carrier Proteins

genetics

metabolism

Cell Nucleus

metabolism

DNA-Binding Proteins

genetics

metabolism

Flowers

anatomy & histology

physiology

Gene Expression Regulation

Plant

Hypocotyl

anatomy & histology

metabolism

Light

Molecular Sequence Data

Morphogenesis

physiology

Nuclear Proteins

genetics

metabolism

Photoperiod

Plant Roots

anatomy & histology

growth & development

Protein Isoforms

genetics

metabolism

Protein Structure

Tertiary

Recombinant Fusion Proteins

genetics

metabolism

Sequence Alignment

Signal Transduction

physiology

Transcription Factors

genetics

metabolism

Two-Hybrid System Techniques

Ubiquitin-Protein Ligases

genetics

metabolism

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ref (ämneskategori)

art (ämneskategori)