Change search
ReferencesLink to record
Permanent link

Direct link
Structural and Functional Evolution of Positively Selected Sites in Pine Glutathione S-Transferase Enzyme Family
Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
2013 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 288, no 34, 24441-24451 p.Article in journal (Refereed) Published
Abstract [en]

Phylogenetic analyses have identified positive selection as an important driver of protein evolution, both structural and functional. However, the lack of appropriate combined functional and structural assays has generally hindered attempts to elucidate patterns of positively selected sites and their effects on enzyme activity and substrate specificity. In this study we investigated the evolutionary divergence of the glutathione S-transferase (GST) family in Pinus tabuliformis, a pine that is widely distributed from northern to central China, including cold temperate and drought-stressed regions. GSTs play important roles in plant stress tolerance and detoxification. We cloned 44 GST genes from P. tabuliformis and found that 26 of the 44 belong to the largest (Tau) class of GSTs and are differentially expressed across tissues and developmental stages. Substitution models identified five positively selected sites in the Tau GSTs. To examine the functional significance of these positively selected sites, we applied protein structural modeling and site-directed mutagenesis. We found that four of the five positively selected sites significantly affect the enzyme activity and specificity; thus their variation broadens the GST family substrate spectrum. In addition, positive selection has mainly acted on secondary substrate binding sites or sites close to (but not directly at) the primary substrate binding site; thus their variation enables the acquisition of new catalytic functions without compromising the protein primary biochemical properties. Our study sheds light on selective aspects of the functional and structural divergence of the GST family in pine and other organisms.

Place, publisher, year, edition, pages
2013. Vol. 288, no 34, 24441-24451 p.
National Category
Biochemistry and Molecular Biology
URN: urn:nbn:se:umu:diva-86639DOI: 10.1074/jbc.M113.456863ISI: 000330612300014OAI: diva2:713204
Available from: 2014-04-22 Created: 2014-03-03 Last updated: 2014-04-22Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Wang, Xiao-Ru
By organisation
Department of Ecology and Environmental Sciences
In the same journal
Journal of Biological Chemistry
Biochemistry and Molecular Biology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 43 hits
ReferencesLink to record
Permanent link

Direct link