Effect of Selection on Amylose and Amylopectin Concentration in Maize (Zea mays L.)

Two cycles of reciprocal recurrent selection at the University of Nigeria, Nsukka shifted the average percentage amylopectin of the eight populations of maize (Zea mays L.) from 74.50 to 81.30 per cent, 74.00 to 82.00 percent , 77.50 to 82.50 percent, 76.00 to 82.00 percent, 77.00 to 82.5 per cent, 74.50 to 82.05 per cent, 75.50 to 82.30 per cent and from 77.00 to 82.32 percent. Selection was not effective in developing high amylose strain. The average percentage amylose of the eight populations of maize decreased from 25.50 to 20.00 percent, 26.00 to 19.30 percent,22.50 to 20.00 percent, 24.00 to 20.10 percent, 23.00 to 19.31 percent, 25.50 to 19.40 percent, 24.50 to 20.41 percent, and 23.00 to 19.23 percent. The developed synthetics can be used as commercial varieties per se, as reservoirs of germplasm for further improvement, and for the extraction of superior inbred lines for use in hybrid maize production.Key words: Reciprocal Recurrent Selection, Amylopectin, Amylose, Maize synthetics, Germplas

Molecular basis for the recognition of 24-(S)-hydroxycholesterol by integrin αvβ3

Abstract A growing body of evidence suggests that oxysterols such as 25-hydroxycholesterol (25HC) are biologically active and involved in many physiological and pathological processes. Our previous study demonstrated that 25HC induces an innate immune response during viral infections by activating the integrin-focal adhesion kinase (FAK) pathway. 25HC produced the proinflammatory response by binding directly to integrins at a novel binding site (site II) and triggering the production of proinflammatory mediators such as tumor necrosis factor-α (TNF) and interleukin-6 (IL-6). 24-(S)-hydroxycholesterol (24HC), a structural isomer of 25HC, plays a critical role in cholesterol homeostasis in the human brain and is implicated in multiple inflammatory conditions, including Alzheimer’s disease. However, whether 24HC can induce a proinflammatory response like 25HC in non-neuronal cells has not been studied and remains unknown. The aim of this study was to examine whether 24HC produces such an immune response using in silico and in vitro experiments. Our results indicate that despite being a structural isomer of 25HC, 24HC binds at site II in a distinct binding mode, engages in varied residue interactions, and produces significant conformational changes in the specificity-determining loop (SDL). In addition, our surface plasmon resonance (SPR) study reveals that 24HC could directly bind to integrin αvβ3, with a binding affinity three-fold lower than 25HC. Furthermore, our in vitro studies with macrophages support the involvement of FAK and NFκB signaling pathways in triggering 24HC-mediated production of TNF. Thus, we have identified 24HC as another oxysterol that binds to integrin αvβ3 and promotes a proinflammatory response via the integrin-FAK-NFκB pathway