Roles of plant homologs of Rab1p and Rab7p in the biogenesis of the peribacteroid membrane, a subcellular compartment formed de novo during root nodule symbiosis.

The peribacteroid membrane (PBM) in legume root nodules is derived from plasma membrane following endocytosis of Rhizobium by fusion of newly synthesized vesicles. We studied the roles of plant Rab1p and Rab7p homologs, the small GTP-binding proteins involved in vesicular transport, in the biogenesis of the PBM. Three cDNAs encoding legume homologs of mammalian Rab1p and Rab7p were isolated from soybean (sRab1p, sRab7p) and Vigna aconitifolia (vRab7p). sRab1p was confirmed to be a functional counterpart of yeast Ypt1p (Rab1p) by complementation of a yeast ypt1-1 mutant. Both srab1 and vrab7 genes are induced during nodulation with the level of vrab7 mRNA being 12 times higher than that in root meristem and leaves. This induction directly correlates with membrane proliferation in nodules. Antisense constructs of srab1 and vrab7, under a nodule-specific promoter (leghemoglobin, Lbc3), were made in a binary vector and transgenic nodules were developed on soybean hairy roots obtained through Agrobacterium rhizogenes-mediated transformation. Both antisense srab1 and vrab7 nodules were smaller in size and showed lower nitrogenase activity than controls. The antisense srab1 nodules showed lack of expansion of infected cells, fewer bacteroids per cell and their frequent release into vacuoles. In contrast, antisense vrab7 expressing nodules showed accumulation of late endosomal structure and multivesicular bodies in the perinuclear region. These data suggest that both Rab1p and Rab7p are essential for the development of the PBM compartment in effective symbiosis.     

Metal Complexes in Cancer Treatment: Journey So Far

Metal complexes in cancer therapy have attracted much interest mainly because metals exhibit unique characteristics, such as redox activity, metal-ligand interaction, structure and bonding, Lewis acid properties etc. In 1965, Barnett Rosenberg serendipitously discovered the metal-based compound cisplatin, an outstanding breakthrough in the history of metal-based anticancer complexes and led to a new area of anticancer drug discovery. Many metal-based compounds have been studied for their potential anticancer properties. Some of these compounds have FDA approval for clinical use, while others are now undergoing clinical trials for cancer therapy and detection. In the present study, we have highlighted the primary mode of action of metallic complexes and all FDA-approved/under clinical trial drugs with reference to cancer treatment. This review also focuses on recent progress on metal-based complexes such as platinum, ruthenium, iron, etc. with potential anticancer activities.     

WRKY transcription factors: evolution,regulation, and functional diversity in plants

Protoplasma - The recent advancements in sequencing technologies and informatic tools promoted a paradigm shift to decipher the hidden biological mysteries and transformed the biological issues...     

Duffy blood group determinants and malaria in India

Two hundred and fiftyeight Muria Gond subjects from Bastar district in Central India and 97 subjects from Delhi were typed for Duffy blood group determinants, and their blood examined for malaria antibodies as well as for presence of malarial parasites. We found the Duffy-negative phenotype in high prevalence among Muria Gonds, while in Delhi no subject was observed to be Duffy-negative. Frequencies of seropositivity for malaria antibodies (the test did not distinguish betweenP. falciparum andP. vivax) were not significantly different among subgroups of Muria Gond individuals with different Duffy blood group phenotypes. Examination of thin and thick blood films did not reveal infection withP. vivax in Duffy-negative individuals. Our results suggest that Duffy-negative individuals, though resistant to infection withP. vivax, are not resistant to infection withP. falcipanun.     

Physical Characterization of Plasmid pMQV10 from a Steroid Biotransforming Strain of Micrococcus

The presence of a single plasmid 8.5 kb in size has been demonstrated in a cholesterol biotransforming strain of Micrococcus. A detailed physical map of the plasmid has been constructed using various restriction enzymes. Streptomycin resistance has been localized on a 1.8-kb fragment of pMQV10.     

Wellness programs: a review of the evidence

OBJECTIVE: To review studies that have examined an association between wellness programs and improvements in quality of life and to assess the strength of the scientific evidence. DATA SOURCES: A MEDLINE search was constructed with the following medical subject headings: "psychoneuroimmunology," "chronic disease" and "health promotion," "chronic disease" and "health behaviour," "relaxation techniques," "music therapy," "laughter," "anger," "mediation" and "behavioural medicine." Searches using the text words "wellness" and "wellness program" were also carried out. References from the primary articles identified in the search and contemporary writing on wellness were also considered. STUDY SELECTION: Selection was limited to randomized controlled trials or prospective studies published in English that involved human subjects and that took place between 1980 and 1996. All studies with an intervention aimed at promoting wellness and measuring outcomes were included, except studies of patients with cancer and HIV and studies of health promotion programs in the workplace. Of the 1082 references initially identified, 11 met the criteria for inclusion in the critical appraisal. DATA EXTRACTION: The following information was extracted from the 11 studies: characteristics of the study population, number of participants (and number followed to completion), length of follow-up, type of intervention, outcome measures and results. All 11 studies were assessed for the quality of their evidence. DATA SYNTHESIS: All studies reported some positive outcomes following the intervention in question, although many had limitations precluding applicability of the results to a wider population. CONCLUSIONS: Despite the suggested benefit associated with wellness programs, the evidence was inconclusive. Whether the composition of the target group or the type of intervention has a role in determining outcomes is unknown. Although trends suggest that wellness programs may be cost-effective, further research is needed for confirmation.     

A comparative study of the membrane structure in different types of muscle fibers in the frog

The muscle membrane of slow and fast fibers in cruralis and iliofibularis muscles and of intermediate fibers in submaxillaris muscle of the frog is studied in freeze-fracture replicas. A comparison of membrane folds, number, size and distribution of caveolae and of intramembrane particles (IMP) is given. In slow muscle fibers, the membrane folds are systematically present at the level of the I zone with a transversal continuity, whereas in fast and intermediate types the membrane folds are small and are randomly distributed. In slow muscle the caveolae are more numerous at the I zone than in the part corresponding to the center of the sarcomere. In fast muscle, small groups of caveolae form linear patterns, and in intermediate fibers the distribution is random. The number of caveolae in slow muscle fibers is two times more than in fast and intermediate fibers. The mean area of caveolae opening is largest in fast and smallest in slow muscle fibers. The number of IMP is significantly different in the three types of fibers, being highest in slow and lowest in intermediate fibers. The different pattern of folds in slow fibers may correspond to the different contractile properties of this fiber type. The presence of double the number of caveolae in slow fibers correlated to the less elaborate T system in this fiber type shows the possibility that slow fibers may be the result of an arrest during development for the performance of a different function. The difference in IMP density in the three muscle fiber types may be interpreted as the difference in their electrical properties.