MeNINV1: An Alkaline/Neutral Invertase Gene of Manihot esculenta, Enhanced Sucrose Catabolism and Promoted Plant Vegetative Growth in Transgenic Arabidopsis

Abstract

Alkaline/neutral invertase (A/N-INV) is an invertase that irreversibly decomposes sucrose into fructose as well as glucose and plays a role in plant growth and development, starch synthesis, abiotic stress, and other plant-life activities. Cassava is an economically important starch crop in tropical regions. During the development of cassava tuber roots, A/N-INV activity is relatively high, which indicates that it may participate in sucrose metabolism and starch synthesis. In this study, MeNINV1 was confirmed to function as invertase to catalyze sucrose decomposition in yeast. The optimal enzymatic properties of MeNINV1 were a pH of 6.5, a reaction temperature of 40 °C, and sucrose as its specific catalytic substrate. VB6, Zn2+, and Pb2+ at low concentrations as well as EDTA, DTT, Tris, Mg2+, and fructose inhibited A/N-INV enzymic activity. In cassava, the MeNINV1 gene was mainly expressed in the fibrous roots and the tuber root phloem, and its expression decreased as the tuber root grew. MeNINV1 was confirmed to localize in chloroplasts. In Arabidopsis, MeNINV1-overexpressing Arabidopsis had higher A/N-INV activity, and the increased glucose, fructose, and starch content in the leaves promoted plant growth and delayed flowering time but did not change its resistance to abiotic stress. Our results provide new insights into the biological function of MeNINV1.

Genetic association analysis in sugarcane (Saccharum spp.) for sucrose accumulation in humid environments in Colombia

“…SUS6 catalyzes the reversible conversion of sucrose to UDP-glucose and fructose for various metabolic pathways [ 65 ], while the enzyme CIN3 cleaves the terminal nonreducing beta-fructofuranoside residues [ 66 ]. CINV2 can regulate sugar-mediated root development by controlling sucrose catabolism in root cells, while CINV1 participates in osmotic stress-induced inhibition of lateral root growth by controlling the concentration of hexose in the cells [ 64 , 67 ]. These enzymes play a central role in the sucrose accumulation process, since sucrose is hydrolyzed by sucrose synthase or invertase in sink tissues and later used for cell growth, development, or sugar storage in the plant [ 21 ].…”

Harnessing Knowledge from Plant Functional Genomics and Multi-Omics for Genetic Improvement

“…In Chinese cabbage, BcSOC1 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1) identified by transcriptome analysis promoted stem elongation, and led to early bolting and flowering [ 22 ]. In another work, overexpression of cassava neutral invertase ( Manihot esculenta ) MeNINV1 in Arabidopsis resulted in increased glucose, fructose, and starch contents in leaves with promoted plant growth and delayed flowering time [ 23 ].…”

Exploring the role of GhN/AINV23: implications for plant growth, development, and drought tolerance

“…N/AINVs have been confirmed to participate in various stages of the plant life cycle, particularly in stress response and root development [ 11 – 18 ]. The gene MeNINV1 , an alkaline/neutral invertase gene derived from Manihot esculenta , could enhance sucrose catabolism and promote vegetative growth in transgenic Arabidopsis plants [ 19 ]. Inhibition of the expression of NtNINV10 decreased the glucose and fructose in tobacco leaves [ 20 ].…”