FIND ARTICLE

TRANSGLUTAMINASES AND THEIR BIOLOGICAL ROLE

Oligomeric and polymeric protein associations often involve purely secondary chemical forces that is, hydrogen bonds, ionic bonds and van der Waals forces. Protein assembly and disassembly can also be regulated by post-translational modifications, such as phosphorylation or dephosphorylation, even in these cases the subunits are not linked covalently. The first transglutaminase enzyme (TGase, EC 2.3.2.13) was recognised on the basis of its ability to catalyse the covalent incorporation of amine into proteins.

POLYAMINE RESEARCH IN PLANT CELL – NEW APPROCHES

Our understanding of the precise role of polyamines in various plant developmental and morphogenetic processes has advanced considerably by the ability to manipulate polyamines biosynthe- tic pathways using polyamines biosynthesis inhibitors, polyamines-mutants and by adopting various transgenic strategies. The cDNA for almost every biosynthesis polyamine pathway enzyme has been isolated and cloned. This review summarizes our current understanding of the genetic control of polyami- ne metabolism and their role in plant cell.

PLANT TRANSGLUTAMINASES

Plant TGases, still unclassified, are widespread in higher and lower plants, in several plant organs and probably different isoforms are differently located in various cell compartments: chloro- plasts, mitochondria, cytoplasm, cell walls. They probably exert a mainly structural or conformational role; however, in chloroplasts and mitochondria their roles might be related to the organelles’ specific metabolisms. Transglutaminases appear related to growth (cell cycle, apical growth, seedling growth), differentiation, programmed cell death and stress.

Polyamines in chloroplasts

Polyamines include detected in the chloroplast Euglena gracilis, Helianthus tuberosus, spinach and corn. When using the HPLC method detected the presence of three major polyamines putrescine, spermidine and spermine in the membranes of spinach leaves tylakoidowych. These polyamines are covalently linked to the PSII reaction center complex and chlorophyll a / b protein constituting the major PSII antenna - LHCII.

The Editorial Board
Andrzej Łukaszyk - przewodniczący, Zofia Bielańska-Osuchowska, Szczepan Biliński, Mieczysław Chorąży, Aleksander Koj, Włodzimierz Korochoda, Leszek Kuźnicki, Aleksandra Stojałowska, Lech Wojtczak

Editorial address:
Katedra i Zakład Histologii i Embriologii Uniwersytetu Medycznego w Poznaniu, ul. Święcickiego 6, 60-781 Poznań, tel. +48 61 8546453, fax. +48 61 8546440, email: mnowicki@ump.edu.pl

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