Biomedical subjects

Atsumi Tsujimoto

Publications and source records attributed to Atsumi Tsujimoto.

5 recordsLinked to original sources

PubMed2004

Effect of exercise on hepatic gene expression in rats: a microarray analysis.

Exercise has various beneficial effects on liver function, enhancing both nutrient metabolism and antioxidant capacity. To explore the molecular mechanisms underlying these changes, we used a high-density cDNA microarray containing probe sets for 2,845 genes to analyze changes of gene transcription in the livers of rats after 4 weeks of running exercise. In comparison with sedentary animals, 105 genes were up-regulated and 86 genes were down-regulated, including genes with unknown functions. In addition, we detected an increase of p38 mitogen-activated protein kinase and protein and of the protein for signal transducer and activator of transcription 3 (stat3), corresponding to the increase of these mRNAs shown by microarray analysis. These results indicate that long-term exercise can alter liver function via changes of gene expression, especially the genes encoding signal transduction proteins such as p38 and stat3.

Animals↗

PubMed2004

Prepro-tachykinin gene expression in the brain of the honeybee Apis mellifera.

We have recently identified a tachykinin-related peptide (AmTRP) from the mushroom bodies (MBs) of the brain of the honeybee Apis mellifera L. by using direct matrix-assisted laser desorption/ionization with time-of-flight mass spectometry and have isolated its cDNA. Here, we have examined prepro-AmTRP gene expression in the honeybee brain by using in situ hybridization. The prepro-AmTRP gene is expressed predominantly in the MBs and in some neurons located in the optic and antennal lobes. cDNA microarray studies have revealed that AmTRP expression is enriched in the MBs compared with other brain regions. There is no difference in AmTRP-expressing cells among worker, queen, and drone brains, suggesting that the cell types that express the prepro-AmTRP gene do not change according to division of labor, sex, or caste. The unique expression pattern of the prepro-AmTRP gene suggests that AmTRPs function as neuromodulators in the MBs of the honeybee brain.

Animals↗

PubMed2003

cDNA microarray analysis of individual Duchenne muscular dystrophy patients.

We have developed a novel cDNA microarray encompassing 3500 genes expressed in skeletal muscle. With this system, we have performed the first study of gene expression in samples from individual patients. We analyzed muscle specimen from individuals with Duchenne muscular dystrophy to identify differences among patients. Among the variably expressed genes, we focused on the expression of the genes encoding HLA-related proteins, myosin light chains and troponin Ts as markers of muscle necrosis and regeneration. The expression patterns of these genes correlated with the severity of dystrophic changes on histological examination. Our cDNA microarray provides a new tool to investigate molecular muscle pathology.

Child, Preschool↗

PubMed2002

Identification of genes expressed preferentially in the honeybee mushroom bodies by combination of differential display and cDNA microarray.

To clarify the molecular basis underlying the neural function of the honeybee mushroom bodies (MBs), we identified three genes preferentially expressed in MB using cDNA microarrays containing 480 differential display-positive candidate cDNAs expressed locally or differentially, dependent on caste/aggressive behavior in the honeybee brain. One of the cDNAs encodes a putative type I inositol 1,4,5-trisphosphate (IP(3)) 5-phosphatase and was expressed preferentially in one of two types of intrinsic MB neurons, the large-type Kenyon cells, suggesting that IP(3)-mediated Ca(2+) signaling is enhanced in these neurons.

Animals↗

PubMed2002

A microarray-based method for detecting methylated loci.

CpG island DNA methylation plays an important role in regulating gene expression in development and carcinogenesis. We developed a new microarray-based method called methylation amplification DNA chip (MAD) for detecting differences in methylation. In this method, only methylated CpG islands from the two samples that we wanted to compare were amplified and used for hybridization. The resource material for the microarray was derived from the methylated DNA library of the sample in which we wanted to detect hypermethylation. Choosing the methylated DNA library as the resource material of the microarray increased the percentage of DNA fragments derived from hypermethylated loci on the microarray.

Animals↗