TFE3 is a bHLH-ZIP-type transcription factor that regulates the mammalian Golgi stress response.

The Golgi stress response is a mechanism by which, under conditions of insufficient Golgi function (Golgi stress), the transcription of Golgi-related genes is upregulated through an enhancer, the Golgi apparatus stress response element (GASE), in order to maintain homeostasis in the Golgi. The molecular mechanisms associated with GASE remain to be clarified. Here, we identified TFE3 as a GASE-binding transcription factor. TFE3 was phosphorylated and retained in the cytoplasm in normal growth conditions, whereas it was dephosphorylated, translocated to the nucleus and activated Golgi-related genes through GASE under conditions of Golgi stress, e.g. in response to inhibition of oligosaccharide processing in the Golgi apparatus. From these observations, we concluded that the TFE3-GASE pathway is one of the regulatory pathways of the mammalian Golgi stress response, which regulates the expression of glycosylation-related proteins in response to insufficiency of glycosylation in the Golgi apparatus.

Bacteriological and chemical evaluation of overseas mineral waters.

Overseas and imported mineral waters were subjected to visual examination, tested for standard plate count and heterotrophic bacteria, and also analyzed to determine the concentrations of several anions and cations. Some products showed turbidity or color, and several had standard plate count and/or heterotrophic bacteria. One imported natural mineral water product had a high level of standard plate count, and the levels differed with the lot. Tests for total coliform bacteria, Escherichia coli, fecal streptococci, and Pseudomonas aeruginosa were negative on additional testing of samples having standard plate counts of more than 100. The fluoride concentration of one European region sample exceeded the production standard of the Food Sanitation Act in Japan (raw water: less than 2 mg/L) and most of the products lacked the warning labels which are mandatory for fluoride concentrations over 0.8 mg/L. These results indicate that none of the raw water for mineral waters was seriously polluted, but insufficient sterilization of the bottle or cap or contamination with air-borne microbes during the production process was probably responsible for the pollution. Attention needs to be paid to fair labeling, such as no sterilization/no sterile filtration and high fluoride concentration.