Aug
12
Mon
2013
Invited Talk: Discovery, engineering and applications of Blue Fish Protein with Red Flourescence @ Sathyam Hall
Aug 12 @ 10:00 am – 10:15 am

RamaswamyS. Ramaswamy, Ph.D.
CEO of c-CAMP, Dean, inStem, NCBS, Bangalore, India


Discovery, engineering and applications of Blue Fish Protein with Red Fluorescence

Swagatha Ghosh, Chi-Li Yu, Daniel Ferraro,  Sai Sudha, Wayne Schaefer, David T Gibson and S. Ramaswamy

Fluorescent proteins and their applications have revolutionized our understanding of biology significantly.  In spite of several years since the discovery of the classic GFP, proteins of this class are used as the standard flag bearers.  We have recently discovered a protein from the fish Sanders vitrius that shows interesting fluorescent properties – including a 280 nm stoke shift and infrared emission.  The crystal structure of the wild type protein shows that it is a tetramer.  We have engineered mutations to make a monomer with very similar fluorescent properties. We have used this protein for tissue imaging as well as for in cell-fluorescence successfully

Ramaswamy (1) Ramaswamy (2) Ramaswamy (3) Ramaswamy (4)

Invited Talk: Biology of plant infection by Magnaporthe oryzae @ Sathyam Hall
Aug 12 @ 12:10 pm – 12:30 pm

bharatBharat B. Chattoo, Ph.D.
Professor, Faculty of Science M.S.University of Baroda, India


Biology of plant infection by Magnaporthe oryzae

The rice blast disease caused by the ascomycetous  fungus  Magnaporthe oryzae is a major constraint in rice production. Rice-M.oryzae is also emerging as a good model patho-system to investigate how the fungus invades and propagates within the host. Identification and characterisation of genes critical for fungal pathogenesis provides opportunities to explore their use as possible targets for development of strategies for combating fungal infection and to better understand the complex process of host-pathogen interaction.

We have used insertional mutagenesis and RNAi based approaches to identify pathogenesis related genes in this fungus. A large number of mutants were isolated using Agrobacterium tumefaciens mediated transformation (ATMT). Characterisation of several interesting mutants is in progress. We have identified a novel gene, MGA1, required for the development of appressoria. The mutant mga1 is unable to infect and is impaired in glycogen and lipid mobilization required for appressorium development. The glycerol content in the mycelia of the mutant was significantly lower as compared to wild type and it was unable to tolerate hyperosmotic stress. A novel ABC transporter was identified in this fungus. The abc4 mutant did not form functional appressoria, was non-pathogenic and showed increased sensitivity to certain antifungal molecules implying the role of ABC4 in multidrug resistance (MDR). Another mutant MoSUMO (MGG_05737) was isolated  using a Split Marker technique; the mutant showed defects in growth, germination and infection. Immuno-fluorescence microscopy revealed that MoSumo is localized to septa in mycelia and nucleus as well as septa in spores. Two Dimensional Gel Electrophoresis showed differences in patterns of protein expression between Wild Type B157 and MoΔSumo mutant.  We also isolated and charaterised mutants in MoALR2 (MGG_08843) and MoMNR2 (MGG_09884). Our results indicate that both MoALR2 and MoMNR2 are Mg2+ transporters, and the reduction in the levels of CorA transporters caused defects in surface hydrophobicity, cell wall stress tolerance, sporulation, appressorium formation and infection are mediated through changes in the key signaling cascades in the knock-down transformants. (Work supported by the Department of Biotechnology, Government of India)