Genetic control of acid phosphate isozymes in Arabidopsis thaliana (L.) heynh

Chromosomal location of isozyme markers in wheat-barley addition lines

The peroxidase (CPX, PER), α-amylase (α-AMY), acid and alkaline phosphatase (PHE, PHS) and esterase (EST) zymogram phenotypes of 'Chinese Spring' wheat, 'Betzes' barley and a number of presumptive 'Betzes' chromosome additions to 'Chinese Spring' were determined. It was found that five disomic chromosome addition lines could be distinguished from one another and from the other two possible lines on the basis of the zymogram phenotypes of these isozymes. The structural genes Cpxe-H1 and Cpxe-H2 were located in 'Betzes' chromosome 1, the Perl-H5 and Perl-H6 in chromosome 2, the α-Amy-H2 and α-Amy-H3 in chromosome 7, the Phs-H5 and Phs-H4 in chromosomes 1 and 3 respectively, the Phe-H2, Phe-H3 and Phe-H4 in chromosome 1, the Phe-H1 in chromosome 3, the Ests-H4, Este-H2 and Ests-H6, Este-H8 in chromosomes 1 and 3 respectively and the Estl-H10 and Estl-H2 structural genes were related to chromosomes 3 and 6 respectively. These gene locations provide evidence of homoeology between 'Betzes' chromosomes 1, 2, 3, 6 and 7 and the rye chromosomes 7, 2, 3, 6 and 5, respectively, and also between 'Betzes' chromosomes 1, 2, 3, 6 and 7 and the 'Chinese Spring' homoeologous groups 7, 2, 3, 6 and 5, respectively.

Esterase and acid phosphatase polymorphism in the fig tree (Ficus carica L.)

The genetics of two enzymatic loci, esterase (Est-D) and acid phosphatase (AcP-A), were studied by means of polyacrylamide gel electrophoresis in the fig tree (Ficus carica L.). Two codominant alleles are described at the Est-D locus and four codominant alleles at the AcP-A locus. Heterozygotes at the AcP-A locus have a hybrid band, thus showing that the AcP-A allozymes, are at least dimer molecules. Both loci are independent of the male sterility factor in F. carica. The polymorphism in four natural populations was investigated for both loci. A significant deficiency of heterozygotes was observed.

Dissociation-recombination of sunflower seed acid phosphatase

Formal genetic studies of sunflower (Helianthus annuus) seed acid phosphatase (ACP, E.C. 3.1.3.2) had suggested that the functional enzyme consists of two polypeptide subunits. The dimeric quaternary structure was demonstrated by dissociation-recombination procedures. Dissociation of electrophoretically distinct homodimers was effected upon freezing of extracts in a pH 8-9 buffer containing 1 M NaCl and 0.1 M 2-mercaptoethanol. Reassociation, as indicated by the formation of the hybrid isozyme, occurred during 12 hr dialysis against a pH 7.0 buffer.

THE GENETIC CONTROL OF SUNFLOWER SEED ACID PHOSPHATASE

Genetic studies indicate that the acid phosphatase isozymes in seeds of the annual sunflower (Helianthus annuus) are specified by a single gene, Acp, having at least four codominant alleles, S, B, I and F. The enzyme is presumably dimeric. The polypeptide subunits in heterozygotes form an intragenic heterodimer in addition to two homodimers. Acp is not linked to either of the genes coding for seed alcohol dehydrogenase, Adh-1 and Adh-2, and these are not linked to each other. Acp therefore provides a molecular marker for a third sunflower linkage group. The estimated molecular weight of the intact, functional enzyme is about 95,000 daltons.