Progress towards elucidating the mechanisms of self-incompatibility in the grasses: further insights from studies in Lolium

TY - JOUR

T1 - Progress towards elucidating the mechanisms of self-incompatibility in the grasses: further insights from studies in Lolium

AU - Klaas, Manfred

AU - Yang, Bicheng

AU - Bosch, Maurice

AU - Thorogood, Daniel

AU - Manzanares, Chloe

AU - Armstead, Ian Peter

AU - Franklin, F. C. H.

AU - Barth, Susanne

N1 - IMPF: 04.03 specialissue: Sexual plant reproduction

PY - 2011/7/27

Y1 - 2011/7/27

N2 - Background and Scope. Self-incompatibility (SI) in flowering plants ensures the maintenance of genetic diversity by ensuring outbreeding. Different genetic and mechanistic systems of SI among flowering plants suggest either multiple origins of SI or considerable evolutionary diversification. In the grasses, SI is based on two loci, S and Z, which are both polyallelic: an incompatible reaction occurs only if both S and Z alleles are matched in individual pollen with alleles of the pistil on which they alight. Such incompatibility is referred to as gametophytic SI (GSI). The mechanics of grass GSI is poorly understood relative to the well-characterized S-RNase-based single-locus GSI systems (Solanaceae, Rosaceae, Plantaginaceae), or the Papaver recognition system that triggers a calcium-dependent signalling network culminating in programmed cell death. There is every reason to suggest that the grass SI system represents yet another mechanism of SI. S and Z loci have been mapped using isozymes to linkage groups C1 and C2 of the Triticeae consensus maps in Secale, Phalaris and Lolium. Recently, in Lolium perenne, in order to finely map and identify S and Z, more closely spaced markers have been developed based on cDNA and repeat DNA sequences, in part from genomic regions syntenic between the grasses. Several genes tightly linked to the S and Z loci were identified, but so far no convincing candidate has emerged.

AB - Background and Scope. Self-incompatibility (SI) in flowering plants ensures the maintenance of genetic diversity by ensuring outbreeding. Different genetic and mechanistic systems of SI among flowering plants suggest either multiple origins of SI or considerable evolutionary diversification. In the grasses, SI is based on two loci, S and Z, which are both polyallelic: an incompatible reaction occurs only if both S and Z alleles are matched in individual pollen with alleles of the pistil on which they alight. Such incompatibility is referred to as gametophytic SI (GSI). The mechanics of grass GSI is poorly understood relative to the well-characterized S-RNase-based single-locus GSI systems (Solanaceae, Rosaceae, Plantaginaceae), or the Papaver recognition system that triggers a calcium-dependent signalling network culminating in programmed cell death. There is every reason to suggest that the grass SI system represents yet another mechanism of SI. S and Z loci have been mapped using isozymes to linkage groups C1 and C2 of the Triticeae consensus maps in Secale, Phalaris and Lolium. Recently, in Lolium perenne, in order to finely map and identify S and Z, more closely spaced markers have been developed based on cDNA and repeat DNA sequences, in part from genomic regions syntenic between the grasses. Several genes tightly linked to the S and Z loci were identified, but so far no convincing candidate has emerged.

KW - Lolium perenne

KW - perennial ryegrass

KW - grasses

KW - Poaceae

KW - self-incompatibility

KW - calcium inhibitors

KW - lanthanum chloride

KW - verapamil

UR - http://hdl.handle.net/2160/8058

U2 - 10.1093/aob/mcr186

DO - 10.1093/aob/mcr186

M3 - Special issue

C2 - 21798860

VL - 108

SP - 677

EP - 685

JO - Annals of Botany

JF - Annals of Botany

SN - 0305-7364

IS - 4

ER -