Amber Afroz

Application of proteomics to investigate stress-induced proteins for improvement in crop protection

Proteomics has contributed to defining the specific functions of genes and proteins involved in plant–pathogen interactions. Proteomic studies have led to the identification of many pathogenicity and defense-related genes and proteins expressed during phytopathogen infections, resulting in the collection of an enormous amount of data. However, the molecular basis of plant–pathogen interactions remains an intensely active area of investigation. In this review, the role of differential analysis of proteins expressed during fungal, bacterial, and viral infection is discussed, as well as the role of JA and SA in the production of stress related proteins. Resistance acquired upon induction of stress related proteins in intact plant leaves is mediated by potentiation of pathogens via signal elicitors. Stress related genes extensively used in biotechnology had been cited. Stress related proteins identified must be followed through for studying the molecular mechanism for plant defense against pathogens.

Comparative proteomic analysis of bacterial wilt susceptible and resistant tomato cultivars

To investigate the molecular mechanisms of bacterial resistance in susceptible and resistant cultivars of tomato, a proteomic approach was adopted. Four cultivars of tomato were selected on the basis of their response to bacterial (Pseudomonas solanacearum) inoculation wherein cultivar Roma and Riogarande, and cultivar Pusa Ruby and Pant Bahr were considered as resistant and susceptible cultivars, respectively. Proteins were extracted from leaves of 3-week-old seedlings of the four cultivars and separated by 2-DE. A total of nine proteins were found to be differentially expressed between the susceptible and resistant cultivars. Amino acid sequences of these proteins were determined with a protein sequencer. The identified proteins belongs to the categories of energy, protein destination and storage, and defense. Of these proteins, a 60kDa chaperonin and an apical membrane antigen were significantly upregulated in resistant cultivars compared with susceptible cultivars. Application of jasmonic acid and salicylic acid resulted in significant changes in levels of apical membrane antigen and protein disulfide-isomerase. Taken together, these results suggest that apical membrane antigen might be involved in bacterial resistance process through salicylic acid induced defense mechanism signaling in tomato plants.

Plant-bacterium interactions analyzed by proteomics

The evolution of the plant immune response has resulted in a highly effective defense system that is able to resist potential attack by microbial pathogens. The primary immune response is referred to as pathogen associated molecular pattern (PAMP) triggered immunity and has evolved to recognize common features of microbial pathogens. In response to the delivery of pathogen effector proteins, plants acquired R proteins to fight against pathogen attack. R-dependent defense response is important in understanding the biochemical and cellular mechanisms and underlying these interactions will enable molecular and transgenic approaches for crops with increased biotic resistance. Proteomic analyses are particularly useful for understanding the mechanisms of host plant against the pathogen attack. Recent advances in the field of proteome analyses have initiated a new research area, i.e., the analysis of more complex microbial communities and their interaction with plant. Such areas hold great potential to elucidate, not only the interactions between bacteria and their host plants, but also of bacteria-bacteria interactions between different bacterial taxa, symbiotic, pathogenic bacteria, and commensal bacteria. During biotic stress, plant hormonal signaling pathways prioritizes defense over other cellular functions. Some plant pathogens take advantage of hormone dependent regulatory system by mimicking hormones that interfere with host immune responses to promote virulence (vir). In this review, it is discussed the cross talk that plays important role in response to pathogens attack with different infection strategies using proteomic approaches.

Determination of proteins induced in response to jasmonic acid and salicylic acid in resistant and susceptible cultivars of tomato.

Jasmonic acid (JA) and salicylic acid (SA) are signaling molecules that play key roles in the regulation of metabolic processes, reproduction, and defense against pathogens. The proteomics approach was used to identify proteins that are induced by JA and SA in the tomato cultivars Roma and Pant Bahr, which are susceptible and resistant to bacterial wilt, respectively. Threonine deaminase and leucine amino peptidase were upregulated, and ribulose-1,5-bisphosphate carboxylase/oxygenase small chain was downregulated by time-course application of JA. Translationally controlled tumor protein was upregulated by time-course application of SA. Protein disulfide isomerase was upregulated by application of either JA or SA. Proteins related to defense, energy, and protein destination/storage are suspected to be responsible for the susceptibility or resistance of the cultivars. Furthermore, in Roma, iron ABC transporter was upregulated by JA and down-regulated by SA. Iron ABC transporter plays a part in the signal transduction of both JA and SA in cultivars of tomato that are resistant to bacterial wilt.

Dermatomycoses: challenges and human immune responses.

The most prevalent skin infections are mainly caused by species of dermatophytes of the genera Trichophyton, Microsporum, and Epidermophyton that infect keratinized tissues and stratum corneum of skin and hair. Besides proteases with putative role of kinases and other enzymes, immune modulators are abundantly secreted during infection as well. The molecular mechanism used by the dermatophytes to infect and counteract the host immune response is not well understood. The defense against infections basically depends on the hosts immune responses to metabolites of the fungi, virulence of the infecting strain or species and anatomical site of the infection. The two aspects of the immune system, the immediate hypersensitivity and delayed-type hypersensitivity against dermatophytes may be crucial to the progression and severity of skin infection. Management of the infection through species identification and molecular diagnostic techniques as well as use of novel targeted drugs in addition to conventional anti-fungal compounds is of great importance in dealing with disease onsets and outbreaks. Here we reviewed the fungal skin infections elucidating their biologic and immunologic characteristics. Reaction to fungal invasion by the infected epithelial tissue on the host side is also discussed. Moreover, determinants of protective immunity and treatment options are focused that could confer long-lasting resistance to infection.

Analyses of the Proteomes of the Leaf, Hypocotyl, and Root of Young Soybean Seedlings

The functions of organs in young soybean seedling were determined by means of proteomic analysis. Extracts from leaves, hypocotyls, and roots were separated by two-dimensional polyacrylamide gel electrophoresis, and the proteins were identified by mass spectrometry and protein sequencing. The identified proteins were categorized into various groups according to their function. The leaf was abundant in proteins associated with energy production (50.0%), the hypocotyl was rich in defense proteins (31.8%), and the root contained defense-related proteins (16.7%) and destination and storage proteins (26.7%). Stem 31-kDa glycoprotein, 20 kDa chaperonin, 50S ribosomal protein, and trypsin inhibitor were common to all three tissues. The sequence information obtained from the soybean proteome should be helpful in predicting the functions of unknown proteins.

Differential proteome analysis of diabetes mellitus type 2 and its pathophysiological complications

The prevalence of Diabetes Mellitus Type 2 (DM 2) is increasing every passing year due to some global changes in lifestyles of people. The exact underlying mechanisms of the progression of this disease are not yet known. However recent advances in the combined omics more particularly in proteomics and genomics have opened a gateway towards the understanding of predetermined genetic factors, progression, complications and treatment of this disease. Here we shall review the recent advances in proteomics that have led to an early and better diagnostic approaches in controlling DM 2 more importantly the comparison of structural and functional protein biomarkers that are modified in the diseased state. By applying these advanced and promising proteomic strategies with bioinformatics applications and bio-statistical tools the prevalence of DM 2 and its associated disorders i-e nephropathy and retinopathy are expected to be controlled.