The human red cell acid phosphatase activity and its statistical evaluation

Summary We examined 396 bloods samples of the five most common phenotypes of the human red cell acid phosphatase (E.C.3.1.3.2). The different enzyme activity of the individual phenotypes was statistically evaluated and an explanation was sought.     

Determination of isozymes of phosphoglycerate-mutase (E.C.2.7.5.3) and enolase (E.C.4.2.1.11) in human erythrocytes.

525 human hemolysates were tested for the isozymic patterns of phosphoglycerate mutase and enolase. Genetic models for interpreting the pherograms are suggested.     

Visualization of stochastic Ca2+ signals in the formed somites during the early segmentation period in intact,normally developing zebrafish embryos

Localized Ca²⁺ signals were consistently visualized in the formed somites of intact zebrafish embryos during the early segmentation period. Unlike the regular process of somitogenesis, these signals were stochastic in nature with respect to time and location. They did, however, occur predominantly at the medial and lateral boundaries within the formed somites. Embryos were treated with modulators of [Ca²⁺]_i to explore the signal generation mechanism and possible developmental function of the stochastic transients. Blocking elements in the phosphoinositol pathway eliminated the stochastic signals but had no obvious effect, stochastic or otherwise, on the formed somites. Such treatments did, however, result in the subsequently formed somites being longer in the mediolateral dimension. Targeted uncaging of buffer (diazo‐2) or Ca²⁺ (NP‐ethyleneglycoltetraacetic acid [EGTA]) in the presomitic mesoderm, resulted in a regular mediolateral lengthening and shortening, respectively, of subsequently formed somites. These data suggest a requirement for IP₃ receptor‐mediated Ca²⁺ release during convergence cell movements in the presomitic mesoderm, which appears to have a distinct function from that of the IP₃ receptor‐mediated stochastic Ca²⁺ signaling in the formed somites.     

Molecular characterisation of resistance against potato wart races 1, 2, 6 and 18 in a tetraploid population of potato (Solanum tuberosum subsp. tuberosum)

Potato wart is caused by the obligate biotrophic fungus Synchytrium endobioticum, which is subject to quarantine regulations due to the production of long persisting spores in the soil and the lack of effective fungicides. The objective of this study was to identify quantitative trait loci (QTL) for resistance against potato wart races (R) 1, 2, 6 and 18 in a tetraploid potato population developed by crossing cv. Saturna (resistant to R1) with cv. Panda (resistant to R1, R2, R6, R18). A total of 92 progenies were used for phenotyping and genotyping. Resistance tests were performed for races 1 and 18 in 2 years and for races 2 and 6 in 1 year on 10 to 20 eyepieces per genotype. Based on amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) markers, linkage maps were established for the female and male parent, respectively. Single marker analysis followed by a multiple regression analysis revealed initial marker–trait associations. The interval mapping routine of TetraploidMap was applied for QTL analysis. A major QTL for resistance against race 1 explaining between 46 % and 56 % of the phenotypic variation was identified near Sen1, a known resistance locus for potato wart race 1 on chromosome XI. Other resistance QTL were detected on chromosomes I (to R2), II (to R6, 18), VI (to R1, 2, 6, 18), VII (to R2, 6, 18), VIII (to R1, 2, 6, 18), X (to R2, 6, 18), XI (to R2, 6, 18) and on an unknown linkage group (to R18) explaining minor to moderate effects of the phenotypic variation. Resistance QTL against different potato wart races often overlapped, particularly concerning races 2, 6 and 18. Overall, this study gives a valuable insight into the complex inheritance of resistance against potato wart.     

Multiple forms of enolase (E.C. 4.2.1.11): their distribution in human tissues.

By means of starch gel electrophoresis, the enzyme enolase was found to be a family of at least 3 isozymes in human tissues. Enolase III shows a strong band in extracts of human brain and in some malignant tumors.     

Hexokinase isozymes in human neoplastic and fetal tissues: the existence of hexokinase II in malignant tumors and in placenta.

The distribution of electrophoretic fractions of hexokinase (HK E.C. 2.7.1.1) in extracts of 53 human primary tumors, homologous normal tissues and fetal organs was investigated. It was found that the fraction HK II is present in every malignant tumor and in placenta tissue.     

Pyruvate kinase isozyme patterns of human neoplastic, fetal and adult tissues.

A method of starch gel electrophoresis is described which enables detection of 6 isozymes of human pyruvate kinase (PK, E.C.2.7.1.40). Comparing the PK-isozyme patterns of 53 diverse human tumors with those of normal adult and fetal organ tissues, it was found that the isozyme PK I is predominant in all malignant tumors as well as in almost all fetal organs.