zur Suche springenzur Navigation springenzum Inhalt springen

Sortieren nach: Erscheinungsjahr Typ der Publikation

Zeige Ergebnisse 1 bis 2 von 2.

Publikation

Smolikova, G.; Shiroglazova, O.; Vinogradova, G.; Leppyanen, I.; Dinastiya, E.; Yakovleva, O.; Dolgikh, E.; Titova, G.; Frolov, A.; Medvedev, S.; Comparative analysis of the plastid conversion, photochemical activity and chlorophyll degradation in developing embryos of green-seeded and yellow-seeded pea (Pisum sativum) cultivars Funct. Plant Biol. 47, 409-424, (2020) DOI: 10.1071/FP19270

Developing seeds of some higher plants are photosynthetically active and contain chlorophylls (Chl), which are typically destroyed at the late stages of seed maturation. However, in some crop plant cultivars, degradation of embryonic Chl remains incomplete, and mature seeds preserve green colour, as it is known for green-seeded cultivars of pea (Pisum sativum L.). The residual Chl compromise seed quality and represent a severe challenge for farmers. Hence, comprehensive understanding of the molecular mechanisms, underlying incomplete Chl degradation is required for maintaining sustainable agriculture. Therefore, here we address dynamics of plastid conversion and photochemical activity alterations, accompanying degradation of Chl in embryos of yellow- and green-seeded cultivars Frisson and Rondo respectively. The yellow-seeded cultivar demonstrated higher rate of Chl degradation at later maturation stage, accompanied with termination of photochemical activity, seed dehydration and conversion of green plastids into amyloplasts. In agreement with this, expression of genes encoding enzymes of Chl degradation was lower in the green seeded cultivar, with the major differences in the levels of Chl b reductase (NYC1) and pheophytinase (PPH) transcripts. Thus, the difference between yellow and green seeds can be attributed to incomplete Chl degradation in the latter at the end of maturation period.
Publikation

Smolikova, G.; Dolgikh, E.; Vikhnina, M.; Frolov, A.; Medvedev, S.; Genetic and Hormonal Regulation of Chlorophyll Degradation during Maturation of Seeds with Green Embryos Int. J. Mol. Sci. 18, 1993, (2017) DOI: 10.3390/ijms18091993

The embryos of some angiosperms (usually referred to as chloroembryos) contain chlorophylls during the whole period of embryogenesis. Developing embryos have photochemically active chloroplasts and are able to produce assimilates, further converted in reserve biopolymers, whereas at the late steps of embryogenesis, seeds undergo dehydration, degradation of chlorophylls, transformation of chloroplast in storage plastids, and enter the dormancy period. However, in some seeds, the process of chlorophyll degradation remains incomplete. These residual chlorophylls compromise the quality of seed material in terms of viability, nutritional value, and shelf life, and represent a serious challenge for breeders and farmers. The mechanisms of chlorophyll degradation during seed maturation are still not completely understood, and only during the recent decades the main pathways and corresponding enzymes could be characterized. Among the identified players, the enzymes of pheophorbide a oxygenase pathway and the proteins encoded by STAY GREEN (SGR) genes are the principle ones. On the biochemical level, abscisic acid (ABA) is the main regulator of seed chlorophyll degradation, mediating activity of corresponding catabolic enzymes on the transcriptional level. In general, a deep insight in the mechanisms of chlorophyll degradation is required to develop the approaches for production of chlorophyll-free high quality seeds.

Diese Seite wurde zuletzt am 11.02.2013 geändert.

IPB Mainnav Search