tailieunhanh - Germin, an oxalate oxidase, has a function in many aspects of plant life

Germin, a molecular marker of wheat embryo germination, is a remarkably proteaseresistant, apoplastic, homopentameric glycoprotein. Different forms of germin found to be related to various aspects of plant development have been discovered. | Turk J Biol 24 (2000) 717–724 © TÜBİTAK Review Article Germin, an Oxalate Oxidase, Has a Function in Many Aspects of Plant Life Mahmut ÇALIŞKAN Mustafa Kemal University, Department of Biology, 31040, Hatay-TURKEY Received: Abstract: Germin, a molecular marker of wheat embryo germination, is a remarkably proteaseresistant, apoplastic, homopentameric glycoprotein. Different forms of germin found to be related to various aspects of plant development have been discovered. Germins were determined in cereals, dicotyledonous angiosperms, gymnosperms and in a prosit, all these proteins are together called germin-like proteins due to their DNA sequence homology. Cereal germins have oxalate oxidase activity, an activity which generates hydrogen peroxide by degrading oxalic acid. Both of these molecules have been implied in the regulation of cell development, differentiation, signalling and defence systems of plants. The germin-like proteins found in dicotyledonous plants do not appear to have oxalate oxidase activity. Recently, germin-like proteins were shown to be related to seed storage proteins (vicilins, legumins), SBS (sucrose-binding proteins) and spherulins. On the basis of these similarities, it was proposed that all these proteins are members of a “superfamily” which are structurally related but functionally distinct proteins. Germin and germin-like proteins seem to be involved in the various important processes of plants including development, osmotic regulation, photoperiodic oscillation, defence and apoptosis. Key Words: Plant development, cell wall, germin, germin-like proteins, oxalate oxidase. Bir Okzalat Oksidaz Olan Germin Bitki Hayatının Pek Çok İşlevinde Rol Almaktadır Özet: Buğday embriyo çimlenmesinin bir göstergesi olan germin; proteaz-dirençli, apoplastik, homopentamerik bir glikoproteindir. Bitki gelişiminin değişik işlevleri ile ilgili farklı germin formları mevcuttur. Tahıllarda, dikotiledonlarda, angiospermlerde ve protist de germin