Inheritance and genetic mapping of two nuclear genes involved in nuclear–cytoplasmic incompatibility in peas (Pisum sativum L.)

Abstract

Genetic analysis was performed to finely map and assess the mode of inheritance of two unlinked nuclear genes Scs1 and Scs2 involved in incompatibility of the nuclear genome of the cultivated pea Pisum sativum subsp. sativum with the cytoplasm of the wild pea of the subspecies P. sativum subsp. elatius, accession VIR320. Based on the segregation of genotypes in the progeny of the test-crosses, we concluded that if the cytoplasm was inherited from the wild pea VIR320, the Scs1 allele from the cultivated pea was gametophyte lethal and sporophyte recessive lethal. The Scs2 allele from the cultivated pea reduced male gametophyte viability. In homozygote, Scs2 from cultivated parent brought about nuclear-cytoplasmic conflict manifested as chlorophyll deficiency, reduction of blade organs, and low pollen fertility of about 20%. In heterozygote, Scs1 and Scs2 genes reduced pollen fertility by ca 50 and 30%, respectively. The Scs1 and Scs2 genes involved in nuclear-cytoplasmic incompatibility were genetically mapped. The distance between the markers bordering Scs1 comprised about 2.5 cM on linkage group III. The map distance between the bordering markers in the neighborhood of Scs2 varied substantially from cross to cross in the range of 2.0-15.1 cM on linkage group V.

A Combined Comparative Transcriptomic, Metabolomic, and Anatomical Analyses of Two Key Domestication Traits: Pod Dehiscence and Seed Dormancy in Pea (Pisum sp.)

“…Four parental genotypes included wild P. elatius JI64 from Turkey and cultivated Afghan landrace P. sativum JI92 both from John Innes Pisum Collection (Norwich, UK); wild P. elatius VIR320 (Bogdanova et al, 2012) from Vavilov Institute Research of Plant Industry (St. Petersburg, Russia) and cultivated P. sativum cv. Cameor from INRA France.…”

“…Furthermore, 126 F 5:6 recombinant inbred lines (RILs) derived from JI64 and JI92 cross (North et al, 1989) were used to establish respective phenotypically contrasting (dormant vs. non-dormant, dehiscent vs. indehiscent) bulks. P. elatius VIR320 differs from other wild peas in relation to the absence of gritty and testa pigmentation, possibly as the result of being either semi-domesticate or hybrid between wild and cultivated pea with unknown origin (Bogdanova et al, 2012). …”

Nuclear-Cytoplasmic Conflict in Pea (Pisum sativum L.) Is Associated with Nuclear and Plastidic Candidate Genes Encoding Acetyl-CoA Carboxylase Subunits

“…In the pea ( Pisum sativum L.), we described nuclear-plastid incompatibility in crosses of wild representatives with cultivated forms [ 20 , 21 ] and genetically mapped two complementary unlinked nuclear genes, Scs1 and Scs2 involved in the conflict [ 22 ]. In crosses of cultivated peas with the wild accession VIR320 as donor of cytoplasm, heterozygotes for both Scs1 and Scs2 were very weak with mosaic chlorophyll deficiency, reduction of blade organs, low pollen and seed fertility, poorly developed roots.…”

“…Unlike Scs2 , Scs1 allele from the cultivated parent was shown to be both sporophyte and male gametophyte lethal in the background of the alien cytoplasm. It was genetically mapped on Linkage Group (LG) III [ 22 ].…”

Genetic and Molecular Genetic Basis of Nuclear-Plastid Incompatibilities

“…In a series of test crosses, it was shown that Scs1 allele from cultivated pea was lethal for sporophytes and male gametophytes in the background of the wild pea cytoplasm. Scs2 allele was not lethal, but was underrepresented among male gametophytes and sporohytes, indicating that some yet unknown genetic interactions brought about lethality to the carriers of this allele [79]. In a number of crosses, Scs1 and Scs2 loci were genetically mapped; Scs1 in an interval of about 2.5 cM on linkage group III, and Scs2 in an interval 2.0 to 15.1 cM varying from cross to cross on linkage group V [79].…”