Cotton is a premium source of natural fiber and is considered Bwhite gold^in the textile industry. Fiber length, strength and fineness are the key considerations for the industry. Longer fibers are machine friendly because they are easily spinnable. Recent advancements in genetic engineering, including the development of DNA markers and quantitative trait loci (QTLs), together with genome sequencing and gene expression profiling, have provided new avenues for improving fiber production and quality. In plants, sucrose synthase (SUS) is the key enzyme that catalyzes the reversible cleavage of sucrose and uridine diphosphate (UDP) into fructose and UDP-glucose. Sucrose is the main mobile sugar in plants moving from source to sink. It regulates resource partitioning between active sinks, especially in cotton embryos and fibers, and therefore is directly involved in determining fiber yield and seed quality. SUS actively takes part in regulating the competition for nutrients among sink tissues through balancing osmotic potentials by providing hexoses and an efficient supply of UDP-glucose the substrate for cellulose synthase. Cotton transformation has been used to improve fiber characteristics by altering cell wall properties through the manipulation of expression of fiber genes. Overexpression of the SUS gene from natural or synthetic origins in cotton can be an excellent way to solve potential problems associated with poor fiber length and other fiber quality traits. Increased SUS activity can result in more hexoses, increasing the osmotic potential and thereby driving the water influx that creates high turgor pressure in fiber cells resulting in enhanced fiber elongation. Moreover, increased SUS gene transcript levels in vegetative tissues of the plant will elevate seedling biomass and seed number. Fiber length and seed number both contribute towards final yield and the SUS genes as key regulators of sink strength in cotton perform this dual function that is directly related to cotton productivity. Hence manipulation of the SUS gene family is considered a promising approach to improve cotton fiber yield and quality. This review focuses on the biochemical and physiological roles of the SUS genes and there value for cotton fiber improvement.

No abstract

The study aims to improve fiber traits of local cotton cultivar through genetic transformation of sucrose synthase ( SuS ) gene in cotton. Sucrose synthase (SuS) is an important factor that is involved in the conversion of sucrose to fructose and UDP-glucose, which are essential for the synthesis of cell wall cellulose. In the current study, we expressed a synthetic SuS gene in cotton plants under the control of a CaMV35S promoter. Amplification of an 813-bp fragment using gene-specific primers confirmed the successful introduction of SuS gene into the genome of cotton variety CEMB-00. High SuS mRNA expression was observed in two transgenic cotton plants, MA0023 and MA0034, when compared to the expression in two other transgenic cotton plants, MA0035 and MA0038. Experiments showed that SuS mRNA expression was positively correlated with SuS activity at the vegetative (54%) and reproductive stages (40%). Furthermore, location of transgene was found to be at chromosome no. 9 in the form of single insertion, while no signal was evident in non-transgenic control cotton plant when evaluated through fluorescent in situ hybridization and karyotyping analysis. Fiber analyses of the transgenic cotton plants showed increases of 11.7% fiber length, 18.65% fiber strength, and up to 5% cellulose contents. An improvement in the micronaire value of 4.21 was also observed in the MA0038 transgenic cotton line. Scanning electron microscopy (SEM) revealed that the fibers of the SuS transgenic cotton plants were highly spiral with a greater number of twists per unit length than the fibers of the non-transgenic control plants. These results determined that SuS gene expression influenced cotton fiber structure and quality, suggesting that SuS gene has great potential for cotton fiber quality improvement.

Our results demonstrated that a combination of ADMSCs and chondrocytes may be a more effective therapeutic strategy against OA than the use of ADMSCs or chondrocytes separately.

No abstract

Genetically modified (GM) plants with insecticidal Bacillus thuringiensis (Bt) genes are widely accepted but their commercial utilization highlights the biosafety issues worldwide. The risk assessment of GM crops demonstrates their impact on the ecosystem as well as non-target organisms (NTOs). Among the NTOs, plant growth promoting rhizobacteria (PGPR) demand more critical experimental studies as they play a significant role in plant growth. A comparative study of Bt with non-Bt cotton rhizosphere was conducted, on selected bacterial strains. During the course of the study, biochemical characterization, auxin biosynthesis and molecular characterization was done to assess the effect of Bt toxins (Cry1Ac and Cry2A) on non-target PGPR strains. A significant decrease (p<0.05) in phosphatase activity was recorded in some of the experimental bacterial strains as compared to those of control strains. However, no significant differences (p>0.05) were observed in other parameters like bacterial population, colony morphologies as well as biochemical activities. Thus, our study demonstrates the safe plantation of Bt crops with respect to soil bacteria.

No abstract

No abstract