The cyclin-dependent kinase inhibitor Orysa;KRP1 plays an important role in seed development of rice

Kip-related proteins (KRPs) play a major role in the regulation of the plant cell cycle. We report the identification of five putative rice (Oryza sativa) proteins that share characteristic motifs with previously described plant KRPs. To investigate the function of KRPs in rice development, we generated transgenic plants overexpressing the Orysa; KRP1 gene. Phenotypic analysis revealed that overexpressed KRP1 reduced cell production during leaf development. The reduced cell production in the leaf meristem was partly compensated by an increased cell size, demonstrating the existence of a compensatory mechanism in monocot species by which growth rate is less reduced than cell production, through cell expansion. Furthermore, Orysa; KRP1 overexpression dramatically reduced seed filling. Sectioning through the overexpressed KRP1 seeds showed that KRP overproduction disturbed the production of endosperm cells. The decrease in the number of fully formed seeds was accompanied by a drop in the endoreduplication of endosperm cells, pointing toward a role of KRP1 in connecting endocycle with endosperm development. Also, spatial and temporal transcript detection in developing seeds suggests that Orysa; KRP1 plays an important role in the exit from the mitotic cell cycle during rice grain formation

Hevein: an antifungal protein from rubber-tree ( Hevea brasiliensis ) latex

Several chitin-binding proteins were isolated from the “bottom fraction” of Hevea brasiliensis (Müll.) Arg. latex. One of these chitin-binding proteins is hevein, a small monomeric protein which strongly resembles the lectin from stinging nettle ( Urtica dioica L.). Like the latter, hevein showed strong antifungal activity against several fungi in vitro. The possible involvement of this protein in the defense against invasion by potentially pathogenic fungi is discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47477/1/425_2004_Article_BF00197797.pd

Isolation and characterisation of plant defensins from seeds of Asteraceae, Fabaceae, Hippocastanaceae and Saxifragaceae

AbstractFrom seeds of Aesculus hippocastanum, Clitoria ternatea, Dahlia merckii and Heuchera sanguinea five antifungal proteins were isolated and shown to be homologous to plant defensins previously characterised from radish seeds and γ-thionins from Poaceae seeds. Based on the spectrum of their antimicriobial activity and the morphological distortions they induce on fungi the peptides can be divided into two classes. The peptides did not inhibit any of three different α-amylases

Fractionation of sialylated oligosaccharides, glycopeptides, and glycoproteins on immobilized elderberry (Sambucus nigra L.) bark lectin

A new plant lectin from elderberry (Sambucus nigra L.) bark, which was shown by immunochemical techniques to bind specifically to terminal Neu5Ac([alpha]2-6)Gal/GalNAc residues of glycoconjugates, was immobilized onto Sepharose 4B (SNA-Sepharose) and its carbohydrate binding properties was determined using a series of standard compounds. Oligosaccharides, glycopeptides, or glycoproteins containing terminal Neu5Ac([alpha]2-6)Gal/GalNAc sequences bound to SNA-Sepharose and were eluted with 50-100 m lactose, whereas those with Neu5Ac([alpha]2-3)Gal/GalNAc failed to bind to this column. Furthermore, the SNA-Sepharose column was capable of resolving two oligosaccharides/glycopeptides based on the number of Neu5Ac([alpha]2-6)Gal units present in each molecule. Application of this technique to two glycoproteins, fetuin and orosomucoid, revealed the presence of microheterogeneity. It was also shown that esterification of the carboxyl group of Neu5Ac units, or branching at the O-3 of the subterminal GalNAc (probably also Gal) destroyed the binding ability of the molecule.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26737/1/0000288.pd

Effects of a wheat bran extract containing arabinoxylan oligosaccharides on gastrointestinal health parameters in healthy adult human volunteers : a double-blind, randomised, placebo-controlled, cross-over trial

Wheat bran extract (WBE) is a food-grade soluble fibre preparation that is highly enriched in arabinoxylan oligosaccharides. In this placebo-controlled cross-over human intervention trial, tolerance and effects on colonic protein and carbohydrate fermentation were studied. After a 1-week run-in period, sixty-three healthy adult volunteers consumed 3, 10 and 0 g WBE/d for 3 weeks in a random order, with 2 weeks' washout between each treatment period. Fasting blood samples were collected at the end of the run-in period and at the end of each treatment period for analysis of haematological and clinical chemistry parameters. Additionally, subjects collected a stool sample for analysis of microbiota, SCFA and pH. A urine sample, collected over 48 h, was used for analysis of p-cresol and phenol content. Finally, the subjects completed questionnaires scoring occurrence frequency and distress severity of eighteen gastrointestinal symptoms. Urinary p-cresol excretion was significantly decreased after WBE consumption at 10 g/d. Faecal bifidobacteria levels were significantly increased after daily intake of 10 g WBE. Additionally, WBE intake at 10 g/d increased faecal SCFA concentrations and lowered faecal pH, indicating increased colonic fermentation of WBE into desired metabolites. At 10 g/d, WBE caused a mild increase in flatulence occurrence frequency and distress severity and a tendency for a mild decrease in constipation occurrence frequency. In conclusion, WBE is well tolerated at doses up to 10 g/d in healthy adults volunteers. Intake of 10 g WBE/d exerts beneficial effects on gut health parameters