Molecular characterization of DNA sequences from the Primula vulgaris S-locus

Abstract

Primula species provide possibly the best known examples of heteromorphic flower development and this breeding system has attracted considerable attention, including that of Charles Darwin. However, despite considerable recent advances in molecular genetics, nothing is known about the molecular basis of floral heteromorphy. The first molecular marker for the Primula S-locus is reported here. This DNA sequence was identified by random amplification of polymorphic DNA (RAPD)-PCR, further defined as a sequence characterized amplified region (SCAR) marker, and subsequently shown to correspond to a restriction fragment length polymorphism (RFLP) that is linked to the thrum allele of the Primula S-locus. The sequence of 8.8 kb of genomic DNA encompassing this thrum-specific RFLP is presented. Analysis of this DNA reveals a highly repetitive sequence structure similar to that found at the S-locus in other species; it also contains sequences similar to elements of a Gypsy-like retrotransposon. The identification of a specific DNA sequence associated with the thrum allele of the Primula S-locus provides the first molecular probe with which to investigate the molecular basis of heteromorphic flower development in Primula.

Genetic Control of Floral Morph and Petal Pigmentation in <i>Linum grandiflorum</i> Desf., a Heterostylous Flax

“…The comparable pin to thrum ratios between the organ and cell lengths indicated that the differences in thrum and pin style lengths were caused by a difference in the cell expansion rate, but not that in cell division. The longer cells of the pin style have also been observed in Primula (Heslop-Harrison et al, 1981;Manfield et al, 2005), indicating that regulation of cell expansion is a key step to determine style length in Primula and Linum. Although the primary regulating factor is unclear and the factors may differ between the (Fig.…”

“…The tight linkage and convergent evolution of SI and floral characteristics in heterostylous plants have been attracting the interest of geneticists and evolutionary biologists since the age of Charles Darwin (Darwin, 1877). Many attempts to isolate the S gene have been reported in Primula, Fagopyrum, and Turnera, but the S gene has never been identified (Labonne and Shore, 2011;Li et al, 2011;Manfield et al, 2005;Yasui et al, 2012). We have also studied heterostyly in Linum in order to isolate the S gene and reported a good S gene candidate (Ushijima et al, 2012).…”

High-resolution mapping of the S-locus in Turnera leads to the discovery of three genes tightly associated with the S-alleles

“…Retroelements have been found associated with the S-locus of Brassica (Cui et al 1999), Papaver (Wheeler et al 2003), Petunia , Antirrhinum (Lai et al 2002) and Malus (Sassa et al 2007). Recently, a Gypsy-like retrotransposon has been identiWed in the S-locus region of distylous P. vulgaris (ManWeld et al 2005). The role, if any, of retroelements around the S-locus is unclear.…”

“…This strategy requires a large mapping population (Martin et al 1993; Barry et al 2008) in addition to molecular markers or genes in close proximity to the locus of interest (Rommens et al 1989;Tanksley et al 1995). Molecular markers very tightly linked to the S-locus have been identiWed in a few distylous species including P. vulgaris (ManWeld et al 2005;Li et al 2007), T. subulata and T. krapovickasii (Labonne et al 2008) and Fagopyrum homotropicum (Aii et al 1998). Screening of a phage library with an S-locus linked molecular marker in P. vulgaris, enabled the characterization of an 8.8-kb genomic DNA sequence containing short tandem repeats, inverted elements, a putative Gypsy-like retrotransposon, but no candidate genes for distyly (ManWeld et al 2005).…”

“…Molecular markers very tightly linked to the S-locus have been identiWed in a few distylous species including P. vulgaris (ManWeld et al 2005;Li et al 2007), T. subulata and T. krapovickasii (Labonne et al 2008) and Fagopyrum homotropicum (Aii et al 1998). Screening of a phage library with an S-locus linked molecular marker in P. vulgaris, enabled the characterization of an 8.8-kb genomic DNA sequence containing short tandem repeats, inverted elements, a putative Gypsy-like retrotransposon, but no candidate genes for distyly (ManWeld et al 2005). To date, the identity of the genes at the S-locus determining distyly is yet to be discovered in any distylous species (Barrett and Shore 2008).…”