Inheritance and linkage relationships of glutamate oxaloacetate transaminase isoenzymes in apple

Abstract

Four zones of enzymatic activity for glutamate oxaloacetate transaminase (GOT) were found in apple tissue. A dimeric gene, GOT-1, determining the fastest migrating zone, was identified. Six alleles were found, including a near null allelle which produced detectable heterodimeric bands but not homodimeric bands. A marked deficit or absence of certain geno-types in all backcrosses and in some crosses between unrelated varieties was attributed to the close linkage (r=0.02±0.005) of GOT-1 with the incompatibility S locus. GOT-1 was also closely linked with the isocitrate dehydrogenase locus IDH-1 (0.03±0.01). Proposed incompatibility genotypes for four cultivars, and the linked GOT-1 alleles are 'Cox': S 1 b/S 2 d, 'Idared': S 3 a/S 4 c, 'Fiesta': S 3 a/S 2 d and 'Kent': S 3 a/S 1 b.

cDNA cloning and molecular analysis of two self-incompatibility alleles from apple

“…Based on data on crossincompatibility between cultivars, scored by the inhibition of pollen tube growth in the style, he attributed an S genotype to a number of cultivars, most of which are not of commercial importance nowadays [25]. Manganaris and Alston [29] observed a phenotypic linkage of the S locus with the iso-enzyme gene glutamate oxaloacetate transaminase (GOT)-1, and deduced the S genotype of a few apple cultivars (not including Golden Delicious). Speranza and Calzoni [37] studied the effect of apple style protein fractions on in vitro pollen development; it was shown that some crude protein fractions, including a fraction containing a 30 kDa glycoprotein not found in other fractions, appeared to contain specific inhibitors of self-pollen tube growth.…”

Genetic Markers and Plant Genetic Resource Management

“…For example, a genetic marker can identify dwarf Malus clones early in their growth (Zhang and Tang 1987). Another isozyme marker in apple has been found tightly linked to the S gene(s) governing incompatibility (Manganaris and Alston 1987). Under certain conditions, nucellar seedlings in Citrus L. spp.…”

Inheritance and Linkage Relationships of Glutamate Oxaloacetate Transaminase Isozymes in Microcitrus.

“…Similarly, three loci control GOT isozymes were reported in citrus (Hirai and Kajiura, 1987), carrot (Westphal and Wricke, 1989) and Populas maximowiczii (Rajora, 1986). The occurrence of null GOT alleles has been reported in citrus at Got-3 (Hirai and Kajiura, 1987), potato at Got-2 (Oliver and Martinez-Zapater, 1985), and apple at Got-1 and Got-2 (Manganaris and Alston, 1987). …”