Cotton fiber provides a distinct picture of cell wall synthesis. It is an epidermal single-cell extension of Cotton plant seed and undergoes three main stages of development, (1) initiation, (2) elongation and (3) maturation. The fiber initiation characterized by thin primary cell wall formation, which is extended afterward by the action of specific non-enzymatic proteins called Expansins, which promote expansion between cellulose microfibrils by cutting the bridges between cellulose and Hemicellulose residues. The elongation phase followed by a compression phase where the secondary cell wall becomes compact and thickened by the deposition of polysaccharides. The fiber development eventually ends up in the maturation phase, attaining the final maximum length of ∼2.5-3.0 cm. However, the most critical periods of Cotton fiber development are cell wall extension and cellulose deposition. Many studies have focused on the role of Expansins in cell wall elongation, but the significance of expansins in cellulose deposition of the secondary cell wall has barely studied to date. This paper, therefore, is a brief review, which will emphasize the role of Expansin in both cell wall extensibility and polysaccharide deposition during the compression phase. However, the versatile role of Expansin proteins in cellulose deposition and cell wall elongation need a more critical experimental approach.

The efficacy of a plant-based vaccine produced in maize by expressing F and HN immunogenic proteins under a seed-specific promoter against NDV genotype VII was assessed using cell-mediated responses in chickens. Using real-time PCR, the mRNA expression of F and HN PCR confirmed maize plants was compared to non-transgenic control plants on a relative basis. F and HN genes mRNA expression was found to be 20 and 60 times higher in corn seeds than in leaves, respectively. In maize seeds, 35 ug/ml of F protein, or 0.6 percent of total protein, and 41 ug/ml of HN protein, or 0.85 percent of total protein, were found using ELISA. The boost in cell-mediated immune response was evaluated in chickens fed with transgenic corn seeds in comparison with control groups. The qPCR analysis showed an increase in the expression of Interleukin-1 (IL-1), Interleukin-2 (IL-2), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interleukin-10 (IL-10), interleukin-15 (IL-15), Interferon-α, Interferon-β, Interferon-γ, and CCL3 when evaluated at 0-day, 7th day, 14th day, 21st day, 28th day and 35th day in chickens receiving transgenic diet as compared to group 1 receiving non-transgenic diet. The increase in cytokines production was comparable with group 3 immunized with conventional market vaccine. Furthermore, anti-NDV antibodies were also found in the serum of chickens given maize containing immunogenic proteins, but not in the serum of chickens fed a normal diet, demonstrating the specificity of the antibodies created through feeding. The data suggest that oral edible vaccinations are more useful in the chicken industry than in injectables.