PubMed Health⌕ Search

Biomedical subjects

Motohiro Shimizu

Publications and source records attributed to Motohiro Shimizu.

7 recordsLinked to original sources
PubMed2004

Mouse 3-phosphoglycerate dehydrogenase gene: genomic organization, chromosomal localization, and promoter analysis.

d-3-Phosphoglycerate dehydrogenase (Phgdh; EC 1.1.1.95) is the first committed enzyme of l-serine biosynthesis in the phosphorylated pathway. We have recently demonstrated that, in developing and mature brain, expression of Phgdh is highly regulated in a cell lineage-specific manner, mainly in neuroepithelial stem cells, radial glia, and astrocytes (J. Neurosci. 21 (2001) 7691; Arch. Histol. Cytol. 66 (2003) 109). To gain insight into the regulatory mechanism of Phgdh expression, we have isolated a mouse genomic clone that contains the entire mouse Phgdh gene. Structural analysis demonstrated that the Phgdh gene spans approximately 27 kilobases (kb) in length and comprises 12 exons with 11 intervening introns. Using fluorescent in situ hybridization (FISH), we mapped the gene to mouse chromosome 3, region F2-F3. Analysis of a 1.8 kb fragment of the 5'-flanking region showed that the classical TATA-box motif near transcription initiation sites was absent. Instead, a GC-rich proximal region containing a potential Sp1 recognition sequence was present; this region is conserved in mouse, rat, and human counterparts. Transient transfection analysis revealed that the cis-acting elements necessary for basal transcription of Phgdh are contained within the -196/+4 proximal sequence of the promoter, in which the conserved Sp1 recognition sites play an important role for basal promoter activity.

5' Flanking Region↗
PubMed2004

Functional analysis of mouse 3-phosphoglycerate dehydrogenase (Phgdh) gene promoter in developing brain.

D-3-Phosphoglycerate dehydrogenase (Phgdh; EC 1.1.1.95) is a necessary enzyme for de novo L-serine biosynthesis via the phosphorylated pathway. Targeted disruption of the mouse Phgdh gene has been shown to result in embryonic lethality, accompanied by severe abnormalities in brain development. Phgdh is expressed exclusively by neuroepithelium and radial glia in developing brain and later mainly by astrocytes. To elucidate the molecular mechanism that regulates such cell-type-specific expression of Phgdh in developing brain, an upstream 3.5-kilobase-pair (kbp) region of the gene harboring the promoter was characterized in primary cultures and transgenic mice. Analysis of Phgdh 5'-nested deletions in transfected cultures indicated that overall reporter luciferase levels were higher in glial cultures than those in neuronal cultures. Although basal promoter activity of the gene appeared to depend on an Sp1 binding sequence residing between -193 and -184 in both glial and neuronal cultures, an upstream 5'-flanking region between -1,794 and -1,095 contributed to up-regulation of Phgdh transcription in a glial-cell-specific manner. In the cerebral cortex of transgenic mouse embryos, the Phgdh promoter-LacZ transgene DNA containing -1,794/+4 promoter sequences directed beta-galactosidase (beta-Gal) expression mainly to Phgdh-positive neuroepithelium and radial glia. This glial preference diminished when beta-Gal expression was driven solely by the upstream 0.2-kbp minimal promoter. However, glial preference of beta-Gal expression was restored by placing the 700-base-pair 5'-DNA segment upstream of the minimal promoter. These observations suggest the presence of cis-acting elements that confer the cell type specificity of Phgdh transcription in the distal promoter region.

Amino Acid Transport System X-AG↗
PubMed2004

[Laser conization].

Explore the source record for details and available documents.

Blood Loss, Surgical↗
PubMed2004

[Sentinel node navigation surgery in uterine cancer].

The Clinical test of sentinel nodes (SNs) in uterine cancer began recently, especially endometrial cancer. In relation to cervical cancer, the detection rate of SN ranged anywhere between 15% to 100% and likewise the sensitivity rate varied from 66% to 100%. Due to these inconclusive results, the data cannot be reliably used for clinical study purposes. Meanwhile, it should be noted that endometrial cancer research has just begun. The tracer used for detection can be roughly classified into an isotope method and a dye method. The isotope method shows a better detection rate, but it can supplemented by using together with the dye method. In Japan, the most commonly reported radiopharmaceutical agent is technetium-99m-labeled phytic acid isotope and 1% isosulfan blue as the dye. In conducting cervical cancer studies, there are many reports of utilizing technetium-99m-labeled phytic acid isotope, injected into 4 different areas of the cervix. Regarding research conducted for endometrial cancer, experiments range from direct injection into the uterine body, injections into the cervix, and hysteroscopic injection. Due to ambiguity in the results, additional clinical testing is required to gather more data.

Female↗