Functional characterization of Arabidopsis thaliana transthyretin-like protein

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Joao Pessoa (Author) Other; Zsuzsa Sarkany (Author) Other; Frederico Ferreira da Silva (Author) Other; Sonia Martins (Author) Other; Maria R Almeida (Author) ICBAS; Jianming M Li (Author) Other; Ana M Damas (Author) ICBAS

Journal

Title: BMC Plant Biology

Vol. 10

Final page: 30

ISSN: 1471-2229

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 19 Citations

Scopus - 25 Citations

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-003-93J

DOI: 10.1186/1471-2229-10-30

Abstract (EN): Background: Arabidopsis thaliana transthyretin-like (TTL) protein is a potential substrate in the brassinosteroid signalling cascade, having a role that moderates plant growth. Moreover, sequence homology revealed two sequence domains similar to 2-oxo-4-hydroxy-4-carboxy-5-ureidoimidazoline (OHCU) decarboxylase (N-terminal domain) and 5-hydroxyisourate (5-HIU) hydrolase (C-terminal domain). TTL is a member of the transthyretin-related protein family (TRP), which comprises a number of proteins with sequence homology to transthyretin (TTR) and the characteristic C-terminal sequence motif Tyr-Arg-Gly-Ser. TRPs are single domain proteins that form tetrameric structures with 5-HIU hydrolase activity. Experimental evidence is fundamental for knowing if TTL is a tetrameric protein, formed by the association of the 5-HIU hydrolase domains and, in this case, if the structural arrangement allows for OHCU decarboxylase activity. This work reports about the biochemical and functional characterization of TTL. Results: The TTL gene was cloned and the protein expressed and purified for biochemical and functional characterization. The results show that TTL is composed of four subunits, with a moderately elongated shape. We also found evidence for 5-HIU hydrolase and OHCU decarboxylase activities in vitro, in the full-length protein. Conclusions: The Arabidopsis thaliana transthyretin-like (TTL) protein is a tetrameric bifunctional enzyme, since it has 5-HIU hydrolase and OHCU decarboxylase activities, which were simultaneously observed in vitro.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10