Allen, Alexandra M. Lexer, Christian Hiscock, Simon J. 2010-02-25 Two related flower-expressed gene copies belonging to the <i>SF21</i> (<i>sunflower-21</i>) gene family have been isolated from <i>Senecio squalidus</i> (Oxford Ragwort, Asteraceae). These gene copies are differentially expressed in pollen and pistil tissues; <i>ORSF21B</i> (<i>Oxford Ragwort SF21B</i>) is expressed exclusively in mature pollen, whereas <i>ORSF21A</i> (<i>Oxford Ragwort SF21A</i>) is expressed in the transmitting tissue of the style, where it is developmentally regulated. Despite differences in expression, the coding regions of <i>ORSF21A</i> and <i>ORSF21B</i> are highly similar. Amino acid sequence alignments of <i>SF21</i> genes from a number of angiosperm species indicate that this gene family is conserved in flowering plants and may play an important role in reproductive processes in a wide range of taxa. Phylogenetic analysis of <i>SF21</i> nucleotide sequence alignments supports this theory, and indicates a complicated history of evolution of this gene family in angiosperms. The putative roles of <i>SF21</i> genes in reproduction and pollen–pistil interactions are discussed. application/pdf https://folia.unifr.ch/global/documents/301753 https://folia.unifr.ch/documents/301753/files/lex_csg.pdf https://folia.unifr.ch/documents/301753/files/lex_csg_sm.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1007/s00497-010-0137-9 info:eu-repo/semantics/openAccess License undefined Sexual Plant Reproduction. - 2010, vol. 23, no. 3, p. 173-186 Pollen Pistil Senecio SF21 Negative differentiation regulator (NDR) info:eu-repo/classification/udc/57 Characterisation of sunflower-21 (SF21) genes expressed in pollen and pistil of Senecio squalidus (Asteraceae) and their relationship with other members of the SF21 gene family http://purl.org/coar/resource_type/c_6501