Starch phosphorylation by starch-related dikinases glucan, water dikinase (GWD) and phosphoglucan, water dikinase (PWD) is a key step in starch degradation. Little information is known about the precise structure of the glucan substrate utilized by the dikinases and about the mechanisms by which these structures may be influenced. A 50-kDa starch-binding protein named EARLY STARVATION1 (ESV1) was analyzed regarding its impact on starch phosphorylation. In various in vitro assays, the influences of the recombinant protein ESV1 on the actions of GWD and PWD on the surfaces of native starch granules were analyzed. In addition, we included starches from various sources as well as truncated forms of GWD. ESV1 preferentially binds to highly ordered, α-glucans, such as starch and crystalline maltodextrins. Furthermore, ESV1 specifically influences the action of GWD and PWD at the starch granule surface. Starch phosphorylation by GWD is decreased in the presence of ESV1, whereas the action of PWD increases in the presence of ESV1. The unique alterations observed in starch phosphorylation by the two dikinases are discussed in regard to altered glucan structures at the starch granule surface.

Starch is the primary storage carbohydrate in most photosynthetic organisms and allows the accumulation of carbon and energy in form of an insoluble and semi-crystalline particle. In the last decades large progress, especially in the model plant Arabidopsis thaliana, was made in understanding the structure and metabolism of starch and its conjunction. The process underlying the initiation of starch granules remains obscure, although this is a fundamental process and seems to be strongly regulated, as in Arabidopsis leaves the starch granule number per chloroplast is fixed with 5-7. Several single, double, and triple mutants were reported in the last years that showed massively alterations in the starch granule number per chloroplast and allowed further insights in this important process. This mini review provides an overview of the current knowledge of processes involved in the initiation and formation of starch granules. We discuss the central role of starch synthase 4 and further proteins for starch genesis and affecting metabolic factors.

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Soy is flavones are phytoestrogens with potential hormonal activity due to their similar chemical structure to 17-B-estradiol. The increasing availability of Soyis flavones throughout the food supply and through use of supplements has prompted extensive research on biological benefits to humans in chronic diseaseprevention and health maintenance. The objective of this study was to assess the effect of consumption of soy bean by pregnant mice on histomorphology of testis, epididymis in the male offspring's. Twenty pregnant female mice at age of six weeks were used as a model for this study.After 40 days (around the puberty age) the animals were sacrificed to get their testes and epididymis each testis and epididymis was weighted, then preparedusing routine histological technique mouse born from mother treated with Soy bean extract (1.5mg daily), Note the absence of mature sperms and the appearance of immature sperms in the lumen seminiferous tubules and the appearance immature sperms connected to the germinal epithelium, and also we note in the epididymis of young male mouse from mother treated with soy bean extract absence of maturesperms in the lumen of the epididymis. Diameters of seminiferous tubules and epididymis together with the thickness of their germinal wall were calculated, these observation indicate that the perinatal exposure of male mice to is flavones affected in testies and epididymis, and they imply that Soy bean has potential implication for testis function.