Biomaterial Database

Cloning, sequencing, structural and molecular biological characterization of placental protein 20 (PP20)/human thiamin pyrophosphokinase (hTPK). 2005

Sz Bellyei, and A Szigeti, and A Boronkai, and Z Szabo, and J Bene, and T Janaky, and L Barna, and K Sipos, and O Minik, and A Kravjak, and R Ohmacht, and B Melegh, and P Zavodszky, and G N Than, and B Sumegi, and H Bohn, and N G Than

Department of Biochemistry and Medical Chemistry, University of Pecs, Pecs, Hungary.

Full-length cDNAs of placental protein 20 (PP20) were cloned by screening a human placental cDNA library, which encode a 243 amino acid protein, identical to human thiamin pyrophosphokinase (hTPK) as confirmed by protein sequence analysis. Genomic alignment showed that the PP20/hTPK gene contains 9 exons. It is abundantly expressed in placenta, as numerous EST clones were identified. As thiamine metabolism deficiencies have been seen in placental infarcts previously, these indicate that PP20/hTPK may have a role in placental diseases. Analysis of the 1kb promoter region showed numerous putative transcription factor binding sites, which might be responsible for the ubiquitous PP20/hTPK expression. This may also be in accordance with the presence of the protein in tissues responsible for the regulation of the exquisite balance between cell division, differentiation and survival. TPK activity of the purified and recombinant protein was proved by mass spectrometry with electrospray ionization. By Western blot, PP20/hTPK was found in all human normal and tumorous adult and fetal tissues in nearly equal amounts, but not in sera. By immunohistochemical and immunofluorescent confocal imaging methods, diffuse labelling in the cytoplasm of the syncytiotrophoblasts and weak staining of the trophoblasts were observed, and the amount of PP20/hTPK decreased from the first trimester to the end of gestation. A 3D model of PP20/hTPK was computed (PDB No.: 1OLY) by homology modelling. A high degree of structural homology showed that the thiamin binding site was highly similar to that of the mouse enzyme, but highly different from the bacterial ones. Comparison of the catalytic centre sequences revealed differences, raising the possibility of designing new drugs which specifically inhibit bacterial and fungal enzymes without affecting PP20/hTPK and offering the possibility for safe antimicrobial therapy during pregnancy.

UI	MeSH Term	Description	Entries
D008956	Models, Chemical	Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.	Chemical Models,Chemical Model,Model, Chemical
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009369	Neoplasms	New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.	Benign Neoplasm,Cancer,Malignant Neoplasm,Tumor,Tumors,Benign Neoplasms,Malignancy,Malignant Neoplasms,Neoplasia,Neoplasm,Neoplasms, Benign,Cancers,Malignancies,Neoplasias,Neoplasm, Benign,Neoplasm, Malignant,Neoplasms, Malignant
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011257	Pregnancy Proteins	Proteins produced by organs of the mother or the PLACENTA during PREGNANCY. These proteins may be pregnancy-specific (present only during pregnancy) or pregnancy-associated (present during pregnancy or under other conditions such as hormone therapy or certain malignancies.)	Placental Proteins,Proteins, Placental,Proteins, Pregnancy
D002277	Carcinoma	A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm and not a synonym for "cancer."	Carcinoma, Anaplastic,Carcinoma, Spindle-Cell,Carcinoma, Undifferentiated,Carcinomatosis,Epithelial Neoplasms, Malignant,Epithelioma,Epithelial Tumors, Malignant,Malignant Epithelial Neoplasms,Neoplasms, Malignant Epithelial,Anaplastic Carcinoma,Anaplastic Carcinomas,Carcinoma, Spindle Cell,Carcinomas,Carcinomatoses,Epithelial Neoplasm, Malignant,Epithelial Tumor, Malignant,Epitheliomas,Malignant Epithelial Neoplasm,Malignant Epithelial Tumor,Malignant Epithelial Tumors,Neoplasm, Malignant Epithelial,Spindle-Cell Carcinoma,Spindle-Cell Carcinomas,Tumor, Malignant Epithelial,Undifferentiated Carcinoma,Undifferentiated Carcinomas
D003001	Cloning, Molecular	The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.	Molecular Cloning
D005260	Female		Females
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
D006367	HeLa Cells	The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for, among other things, VIRUS CULTIVATION and PRECLINICAL DRUG EVALUATION assays.	Cell, HeLa,Cells, HeLa,HeLa Cell