Biomedical subjects

G Kispal

Publications and source records attributed to G Kispal.

39 records · Page 3Linked to original sources

PubMedDate not supplied

Mitochondrial ABC transporters.

In contrast to bacteria, mitochondria contain only a few ATP binding cassette (ABC) transporters in their inner membrane. The known mitochondrial ABC proteins fall into two major classes that, in the yeast Saccharomyces cerevisiae, are represented by the half-transporter Atm1p and the two closely homologous proteins Mdl1p and Mdl2p. In humans two Atm1p orthologues (ABC7 and MTABC3) and two proteins homologous to Mdll/2p have been localized to mitochondria. The Atm1p-like proteins perform an important function in mitochondrial iron homeostasis and in the maturation of Fe/S proteins in the cytosol. Mutations in ABC7 are causative of hereditary X-linked sideroblastic anemia and cerebellar ataxia (XLSA/A). MTABC3 may be a candidate gene for the lethal neonatal syndrome. The function of the mitochondrial Mdl1/2p-like proteins is not clear at present with the notable exception of murine ABC-me that may transport intermediates of heme biosynthesis from the matrix to the cytosol in erythroid tissues.

ATP-Binding Cassette Transporters↗

PubMedDate not supplied

Cloning and sequencing of human oncodevelopmental soluble placental tissue protein 17 (PP17): homology with adipophilin and the mouse adipose differentiation-related protein.

Using a monospecific anti-PP17 antiserum, we detected 4 different molecular-weight PP17 immunoreactive proteins (31,500 kD PP17a, 48, 000 kD PP17b, 60,900 kD PP17c and 74,000 kD PP17d) in different normal adult and fetal human tissues, and in term placenta, by chemiluminescence Western blot analysis. These proteins are overexpressed in cervix carcinoma tissue. Furthermore, increased amounts of PP17b are secreted into the circulation in cervix carcinoma patients; after radical surgery, PP17b serum levels are decreased, and the protein probably has an oncodevelopmental significance. cDNAs were isolated from a human placental cDNA library with the monospecific anti-PP17 antiserum. Sequence analysis of the clones showed that they encode for the 251 residue long PP17a variant, which is identical to the previously isolated and characterized PP17 antigen described in 1983. An alignment search of the protein databank showed that PP17a is homologous to human adipophilin and mouse adipose differentiation-related protein. PP17c turned out to be a dimer of PP17a, while PP17b and PP17d immunoreactive proteins recently detected on Western blots require further investigations.

Adult↗

PubMedDate not supplied

Is placental tissue protein 17b/TIP47 a new factor in cervical cancer genesis?

We identified novel members of the placental tissue protein 17 (PP17) protein family which consists of different-size variants of PP17; cDNAs of PP17a and PP17b variants have also been cloned and sequence analyzed. By Western-blot analysis in cervical carcinoma tissues we found overexpression of PP17b. Compared to healthy controls a mean five-fold increase in the amount of PP17b was also detected in the sera of untreated cervical carcinoma patients, which declined after radical operations. In our recent findings, in sera of inoperable cervical carcinoma patients, we also found elevated PP17b levels which did not change after irradiation. By Northern-blot analyses we confirmed PP17b overexpression in cervical carcinoma tissues and also the alternative splicing of PP17 mRNAs in various normal human tissues. Presently, the amino acid sequence of TIP47--a mannose-6-phosphate receptor cargo selection device--turned out to be identical to that of PP17b. Due to its oncodevelopmental function, PP17b/TIP47 is more than likely to be connected to HSV-2 infection, which is probably one of the main etiopathogenic agents of cervical carcinoma along with the HPV virus, and may open a new trend in the research of pathological processes in human uterine cervical cancer.

Blotting, Northern↗