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Parkinson's disease ( PD) is an age-related, neurodegenerative motor disorder characterized by progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta and presence of α-synuclein-containing protein aggregates. Mutations in the mitochondrial Ser/Thr kinase PTEN-induced kinase 1 ( PINK1) are associated with an autosomal recessive familial form of early-onset PD. Recent studies have suggested that PINK1 plays important neuroprotective roles against mitochondrial dysfunction by phosphorylating and recruiting Parkin, a cytosolic E3 ubiquitin ligase, to facilitate elimination of damaged mitochondria via autophagy-lysosomal pathways. Loss of PINK1 in cells and animals leads to various mitochondrial impairments and oxidative stress, culminating in dopaminergic neuronal death in humans. Using a 2-D polyacrylamide gel electrophoresis proteomics approach, the differences in expressed brain proteome and phosphoproteome between 6-month-old PINK1-deficient mice and wild-type mice were identified. The observed changes in the brain proteome and phosphoproteome of mice lacking PINK1 suggest that defects in signaling networks, energy metabolism, cellular proteostasis, and neuronal structure and plasticity are involved in the pathogenesis of familial PD. [ABSTRACT FROM AUTHOR]

Mycobacterium tuberculosis is a causative agent of tuberculosis ( TB). The ability of M. tuberculosis to be quiescent in the cell has caused the emergence of latent infection. A comprehensive proteomic analysis of M. tuberculosis H37 Rv over three growth phases, namely mid-log (14-day culture), early stationary (28-day culture), and late stationary (50-day culture), was performed in order to study the change in proteome from the mid-log phase to late-stationary phase. Combination methods of two-dimensional electrophoresis (2- DE) and tandem mass spectrometry were used to generate proteome maps of M. tuberculosis at different growth phases. Ten proteins were detected differentially expressed in the late-stationary phase compared with the other two phases. These proteins were SucD, TrpD, and Rv2161c, which belong to metabolic pathway proteins; FadE5, AccD5, DesA1, and Rv1139c are proteins involved in cell wall or lipid biosynthesis, whereas TB21.7 and Rv3224 are conserved hypothetical proteins with unknown function. A surface antigen protein, DesA1, was not detectable in the late-stationary phase, although present in both log and early-stationary phases. The changes in the expression levels of these proteins were in line with the growth environment changes of the bacteria from mid-log phase to late-stationary phase. The information gathered may be valuable in the intervention against latent TB infection. [ABSTRACT FROM AUTHOR]

Expression proteomics has become, in recent years, a key genome-wide expression approach in fundamental and applied life sciences. This postgenomic technology aims the quantitative analysis of all the proteins or protein forms (the so-called proteome) of a given organism in a given environmental and genetic context. It is a challenge to provide effective training in this area due to its demanding laboratory procedures and laborious computational data analysis. However, the effective training of undergraduates and postgraduates in this field is highly recommended to prepare them for the challenges of postgenomic research and of medical, industrial and other economical activities. Since 2004, the area of Biological Sciences at the Department of Chemical and Biological Engineering of lnstituto Superior Técnico (1ST) has been teaching Expression Proteomics to undergraduate and postgraduate students in three formats: 1) as modules of curricular units (CU), in particular of Functional Genomics and Bioinformatics (FGB), offered as a mandatory CU to 1ST Biological Engineering or Biotechnology Master courses students, or as an elective CU to other MSc courses with a biological component and to the MSc in Information Systems and Computer Engineering; the topic is also part of the PhD program in Biotechnology; 2) as mentored coaching, in which 1ST students integrate ongoing research programs at the Biological Sciences Research Group of IBB at 1ST; and 3) as intensive thematic courses open to the external community. In this article, educational programs and teaching methodologies and tools that we have been using are outlined, from the wet-lab to the laptop. The current role of quantitative proteomics in biological research, with emphasis on microbial stress response and on biomedical and biotechnological applications, is addressed, as a case-study, anchored on our group research activities. [ABSTRACT FROM AUTHOR]