ROP Interactive Partners are Involved in the Control of Cell Division Patterns in Arabidopsis Leaves.

Animal Rho GTP-binding proteins and their plant counterparts, Rho of plants (ROPs), regulate cell polarity, but they do so through different effector proteins. A class of ROP effectors, interactor of constitutive active ROPs (ICRs)/ROP interactive partners (RIPs), has been implicated in diverse biological processes; however, there are limited analyses of RIP loss-of-function mutants. Here, we report an analysis of the functions of the Arabidopsis thaliana RIPs in the leaf epidermis. Green Fluorescent Protein (GFP) fusion proteins of all the RIPs colocalized to cortical microtubules. RIP1, RIP3 and RIP4, but not RIP2 and RIP5, colocalized with the preprophase band (PPB), spindles and phragmoplasts. RIP2 and RIP5 did not colocalize with the PPB, spindles or phragmoplasts even when they were expressed under a promoter active in proliferative cells, indicating that there are differences among RIP protein properties. The overexpression of RIP1 or RIP4 resulted in the fragmentation of cortical microtubules, and the rip1 2 3 4 5 quintuple mutant showed increased growth rate of microtubules at their plus ends compared with the wild type. The rip1 2 3 4 5 mutant leaves and petals were narrow, which was explained by the decreased cell number along the transverse axis compared with that of the wild type. The rip1 2 3 4 5 mutant leaf epidermis possessed fewer PPBs oriented close to the long axis of the leaf compared with wild type, indicating the involvement of RIPs in cell division plane regulation and leaf shape determination.

The study of ethanol extract of Epilobium angustifolium L. on blood sugar level in type II diabetic rats.

Epilobium angustifolium (EA) is well known as a traditional medicinal plant in many countries with multiple health effects. However, the chemical composition and anti-diabetic effect of EA has not been reported. In our study, the composition and anti-diabetic effects of ethanol extracts from EA in vivo and in streptozotocin (STZ)-induced type II diabetic rats were investigated. EA ethanol extracts exhibited protection effect on H2O2 induced oxidative stress damage INS-1 cells, reduce the body weight loss, blood glucose level and increase insulin level when compared with those of diabetic rats. Following 21 days of EA treatment at 9.2 and 18.4mg/kg, BW increased by 15.85% and 15.53%, respectively, which were extremely higher than diabetic group (9.50%). The fasting blood glucose level of EA 9.2mg/kg group rats significantly decreased by 60.43% and insulin level increased by 2.78 times, respectively. Corresponding to that, the fasting blood glucose level of EA 18.4mg/kg group rats decreased by 52.61% and insulin level increased by 2 times, respectively. Collectively our data suggest that ethanol extract of EA has remarkably hypoglycemic effect in type 2 diabetes and EA might be a promising functional food or medicine for T2DM treatment.