Mucoepidermoid carcinoma is one of the typical salivary gland malignancies rich in mucin. Mucin1 (MUC1) has been researching for a long ago as a tumor marker for determining diagnosis and prognosis, and moreover O-glycans are changed with malignancy. We performed O-glycans analysis of mucin expression in mucoepidermoid carcinoma and normal salivary glands using supported molecular matrix electrophoresis (SMME). As a result, the core 2 type glycans, (Hex)₂(HexNAc)₂(NeuAc)₁ and (Hex)₂(HexNAc)₂(NeuAc)₂, were found to be significantly abundant glycans of MUC1 in Mucoepidermoid carcinoma. This time, we will report on these series of studies.

The production of heterologous proteins is an important procedure for biologists in basic and applied sciences. A variety of cell-based and cell-free protein expression systems are available to achieve this. The expression system must be selected carefully, especially for target proteins that require post-translational modifications. In this study, human Src family kinases were prepared using six different protein expression systems: 293 human embryonic kidney cells, Escherichia coli, and cell-free expression systems derived from rabbit reticulocytes, wheat germ, insect cells, or Escherichia coli. The phosphorylation status of each kinase was analyzed by Phos-tag SDS-PAGE. The kinase activities were also investigated. In the eukaryotic systems, multiple phosphorylated forms of the expressed kinases were observed. In the rabbit reticulocyte lysate system and 293 cells, differences in phosphorylation status between the wild type and kinase-dead mutants were observed. Whether the expressed kinase was active depended on the properties of both the kinase and each expression system. In the prokaryotic systems, Src and Hck were expressed in autophosphorylated active forms. Clear differences in post-translational phosphorylation among the protein expression systems were revealed. These results provide useful information for preparing functional proteins regulated by phosphorylation.

Leucine-rich repeat kinase 2 (LRRK2) is one of the responsible gene products for familial Parkinson disease. Recent discoveries have elucidated that LRRK2 is involved in regulating intracellular vesicle trafficking by phosphorylating Rab GTPases. Based on the migration pattern on a blue-native PAGE gel, it has been believed that LRRK2 mainly exists as a dimer. However, I undertook a series of biochemical experiments using BN-PAGE as well as other methods and concluded that LRRK2 predominantly exists as a monomer. In this review, I summarized the biochemical analyses on the dimerization state of LRRK2 and its functional significance.

In living systems, there are diverse enzymes whose malfunctions are often related to the progression of diseases. In this study, we have established the line of methodologies to globally study the enzymatic activities in living systems and to characterize the altered activities in relation to diseases. The “enzymomics” study identified the altered activities of endopeptidases in tumor tissues and altered phosphatase activities in blood samples of tumor patients.

Capillary electrophoresis-mass spectrometry (CE-MS) is often used for metabolomics, including small polar molecules, such as amino acids, organic acids, and nucleic acids. As those metabolites have the roles of taste and nutritional functions, metabolomics has been expected to contribute to food and agricultural fields. However, the optimization of those sample preparation and analytical conditions was required depending on the variations in sample and conditions. The standard guideline for agricultural metabolomics are awaited. Here, we demonstrated three types of sample disruption and extraction methods as normal sample preparations. Moreover, the gentle CE sample injection and the large MS data sampling points contribute to the stable CE-MS analysis.

High-value-added meat such as Japanese black beef and brand pork is developed by mating lineages and devising breeding conditions. On the other hand, meat camouflage and the difficulty of creating excellent strains need to be solved. Therefore, a new method, that can analyze genetic and environmental factors at once, can be expected to achieve the efficient excellent breeding and brand meat camouflage appraisal. In this article, we would like to repot the investigation of proteomic approach to branded meat appraisal and a promising selection method of excellent breeding pigs. Two-dimentional DIGE (2D-DIGE) and MALDI-TOF-MS analyses showed that proteins related to glycolysis can be the great maker candidates for distinguishing branded pork. Furthermore, proteome analysis using serum samples of Duroc and Large White pigs showed the possibility of a new individual identification method and excellent breeding value evaluation method.