Title : Molecular regulation of food crop and medicinal plant biochemical pathways under mineral nutrient limitations
Abstract:
Plants naturally grow in degraded soils with mineral nutrient limitations. Close to 800 million people in the world live in rural areas and rely on crop production on degraded soil to put food on their dining tables. More than 500 million smallholder farmers and gardeners produce most of the world’s fresh food, phyto-medicines, and feed. Limited resource farmers lack the financial power to purchase sufficient fertilizers and pesticides for their crops. But most of the time their crops and medicinal plants still produce lots of nutritious biomass food and feed stuff yields. Most studies in plant physiology had focused on the transcriptional and translational changes associated with mineral nutrient limitations but did not explain the molecular mechanisms that created the differential abundance of mRNAs, proteins, and enzyme activities. We have recently confirmed in both in vitro and in vivo studies how superfluous total RNAs are instantly degraded when plants are subjected to soil mineral nutrient limitations. The mechanism is that plant glutamate dehydrogenase (GDH) synthesizes specific panels of non-genetic code-based RNA enzymes in response to soil mineral nutrient compositions and concentrations, xenobiotics, soil pH and temperature changes etc. The nascent GDH-synthesized RNA enzymes swiftly cleanse out unnecessary and superfluous mRNAs, tRNAs, and rRNAs (genetic code-based RNAs) thereby minimizing the wastage of metabolic energy in the synthesis of unnecessary proteins, but optimizing the synthesis of needed amino acids, proteins and enzymes that assure development, nutritious biomass phytochemical accumulation and survival of the crop despite the harsh environment. The G+C contents of GDH-synthesized RNAs are wider and different from those of genetic code-based RNA, and are accordingly more stable electrostatically than total RNA; superfluous total RNA degradation being also different than the RNase, and the RISH/RITS-dependent double-stranded silencing of complementary RNAs (siRNA, miRNA, shRNA). GDH-synthesized RNA enzyme function is thus independent of, above and beyond the genetic code. When Arachis hypogaea was subjected to stoichiometric mineral nutrient limitations, the mRNA encoding phosphate translocator was degraded thus diverting chloroplastic triose phosphates to starch synthesis and export as maltose to the cytoplasm for utilization in cellulose biosynthesis biomass accumulation. Accordingly, the peanuts produced substantially more nutritious pod yields (9418-9822 kg per hectare) compared with the USA peanut producer yield (3184-5936 kg per hectare). The research project is helping smallholder farmers to further increase, double, and optimize nutritious crop yields that assure more farm income and more agriculture jobs. Superfluous total RNA degradation in Zea mays, Vigna unguiculata, Arachis hypogaea, and Phyla dulcis will be discussed as the biochemically proven molecular regulation that support the agriculture innovation capacity of gardeners and smallholder farmers. The discoveries especially help botany, ethno-medicinal pharmacology, agronomy, analytical biochemistry, and plant biology to reconfigure the design of plant projects and to more correctly interpret results, outcomes, and outputs because plant biochemical pathways are dramatically altered in response to the swift degradation of superfluous total RNAs; resulting to the massive accumulation of nutritious biomass and of human health beneficial phytochemicals.
