Chlorophylls regulations

Kim J, Eichacker LA, Rudiger W et al. Chlorophyll regulates accumulation of the plastid-encoded chlorophyll proteins P700 and D1 by increasing apoprotein stability. Plant Physiol 1994 104 907-916. 

Whereas the biosynthesis of chlorophylls a and b in higher plants has been described in detail, the synthesis and regulation of related substances found in less well-known algal groups and lower plants are largely unknown and will be areas of scientific interest in the future. Different and new types of chlorophylls and related substances have been reported and little is known about their possible biological... 

Thomas, H., Chlorophyll a symptom and a regulator of plastid development. New PhytoL, 136, 163, 1997. 

However, this accumulation has not been unequivocally proven. The recent identihcation of urobilinogenoidic linear tetrapyrroles in extracts from primary leaves of barley indicated that further degradation of the v-NCC 1 can take place. While the monoxygenation of pheophorbide a in the earlier phases of chlorophyll breakdown in higher plants appears to be a remarkably stringent entry point, the rather diverse structures of NCCs may indicate that the later phases of the detoxi-hcation process follow less strictly regulated pathways." ... 

Copper is an essential micronutrient required in the growth of both plants and animals. In humans, it helps in the production of blood haemoglobin. In plants, copper is an important component of proteins found in the enzymes that regulate the rate of many biochemical reactions in plants. Plants would not grow without the presence of these specific enzymes. Research projects show that copper promotes seed production and formation, plays an essential role in chlorophyll formation and is essential for proper enzyme activity, disease resistance and regulation of water in plants (Rehm and Schmitt, 2002). 

Sabater S, Artigas J, Duran C, Pardos M, Romani AM, Tomes E, YUa I (2008) Longitudinal development of chlorophyll and phytoplankton assemblages in a regulated large river (the Ebro River). Sci Total Environ 404 196-206... 

U. Johanningmeier, S. H. Howell (1984) Regulation of light-harvesting chlorophyll-binding protein mRNA accumulation in Chlamydomonas reinhardtii. Possible involvement of chlorophyll synthesis precursors. J. Biol. Chem., 259 13541-13549... 

During drought stress, ABA regulates stomatal closure, whereas increased ethylene production has an inhibitory influence on ABA action. An inhibition of ethylene synthesis delays drought-associated chlorophyll loss, supporting the role of ethylene in drought-induced senescence. °°... 

Genes down-Rice regulated by low temperature Rubisco ssu Cab Chlorophyll binding protein Hahn Walbot, 1989... 

C02 + H20 = [CH20] + 02 follows in molar ratio the rule C02 Corg 02 = 1 1 1. The rate of atmospheric C02 sink under present biospheic conditions is 145 kgC per 1kg of chlorophyll. This level of sink is eventually the parameter that regulates the quality of life. 

Gough. Genetic regulation of chlorophyll synthesis analyzed with mutants in barley. Science 184 800-802, 1974. 

Leavitt, PR. (1993) A review of factors that regulate carotenoids and chlorophyll deposition and fossil pigment abundance. J. Paleolimnol. 1, 201-214. 

Because of the widespread occurrence of peroxidase in plant tissues, Nagle and Haard (1975) have suggested that it plays an important role in the development and senescence of plant tissues. It plays a role in biogenesis of ethylene in regulating ripening and senescence in the degradation of chlorophyll and in the oxidation of indole-3-acetic acid. 

Leaf senescence is characterized by loss of chlorophyll, leaf yellowing, degradation of proteins, membrane lipids, and RNA, and recycling to young tissues.453 Delay of leaf senescence by exogenous application of cytokinins has been confirmed by numerous studies,454 suggesting that cytokinins are key components in the regulation of leaf senescence. 

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