Interspecific hybrid ancestry of a plant adaptive radiation: Allopolyploidy of the Hawaiian silversword alliance (Asteraceae) inferred from floral homeotic gene duplications

M. Barrier, B. G. Baldwin, R. H. Robichaux, M. D. Purugganan

Research output: Contribution to journalArticle

Abstract

The polyploid Hawaiian silversword alliance (Asteraceae), a spectacular example of adaptive radiation in plants, was shown previously to have descended from North American tarweeds of the Madia/Raillardiopsis group, a primarily diploid assemblage. The origin of the polyploid condition in the silversword alliance was not resolved in earlier biosystematic, cytogenetic, and molecular studies, apart from the determination that polyploidy in modem species of Madia/Raillardiopsis arose independent of that of the Hawaiian group. We determined that two floral homeotic genes, ASAP3/TM6 and ASAP1, are found in duplicate copies within members of the Hawaiian silversword alliance and appear to have arisen as a result of interspecific hybridization between two North American tarweed species. Our molecular phylogenetic analyses of the ASAP3/TM6 loci suggest that the interspecific hybridization event in the ancestry of the Hawaiian silversword alliance involved members of lineages that include Raillardiopsis muirii (and perhaps Madia nutans) and Raillardiopsis scabrida. The ASAP1 analysis also indicates that the two species of Raillardiopsis are among the closest North American relatives of the Hawaiian silversword alliance. Previous biosystematic evidence demonstrates the potential for allopolyploid formation between members of the two North American tarweed lineages; a vigorous hybrid between R. muirii and R. scabrida has been produced that formed viable, mostly tetraporate (diploid) pollen, in keeping with observed meiotic failure. Various genetic consequences of allopolyploidy may help to explain the phenomenal evolutionary diversification of the silversword alliance.

Original languageEnglish (US)
Pages (from-to)1105-1113
Number of pages9
JournalMolecular Biology and Evolution
Volume16
Issue number8
StatePublished - 1999

Fingerprint

Argyroxiphium
Asteraceae
adaptive radiation
Polyploidy
Gene Duplication
homeotic genes
allopolyploidy
Homeobox Genes
Modems
gene duplication
ancestry
Madia
Genes
Radiation
Diploidy
gene
polyploidy
cytogenetics
interspecific hybridization
Pollen

Keywords

  • Inflorescence
  • MADS-box

ASJC Scopus subject areas

  • Genetics
  • Biochemistry
  • Genetics(clinical)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Ecology, Evolution, Behavior and Systematics
  • Agricultural and Biological Sciences (miscellaneous)
  • Molecular Biology

Cite this

@article{74612da3ca374fd4804cc9d64b688ab7,
title = "Interspecific hybrid ancestry of a plant adaptive radiation: Allopolyploidy of the Hawaiian silversword alliance (Asteraceae) inferred from floral homeotic gene duplications",
abstract = "The polyploid Hawaiian silversword alliance (Asteraceae), a spectacular example of adaptive radiation in plants, was shown previously to have descended from North American tarweeds of the Madia/Raillardiopsis group, a primarily diploid assemblage. The origin of the polyploid condition in the silversword alliance was not resolved in earlier biosystematic, cytogenetic, and molecular studies, apart from the determination that polyploidy in modem species of Madia/Raillardiopsis arose independent of that of the Hawaiian group. We determined that two floral homeotic genes, ASAP3/TM6 and ASAP1, are found in duplicate copies within members of the Hawaiian silversword alliance and appear to have arisen as a result of interspecific hybridization between two North American tarweed species. Our molecular phylogenetic analyses of the ASAP3/TM6 loci suggest that the interspecific hybridization event in the ancestry of the Hawaiian silversword alliance involved members of lineages that include Raillardiopsis muirii (and perhaps Madia nutans) and Raillardiopsis scabrida. The ASAP1 analysis also indicates that the two species of Raillardiopsis are among the closest North American relatives of the Hawaiian silversword alliance. Previous biosystematic evidence demonstrates the potential for allopolyploid formation between members of the two North American tarweed lineages; a vigorous hybrid between R. muirii and R. scabrida has been produced that formed viable, mostly tetraporate (diploid) pollen, in keeping with observed meiotic failure. Various genetic consequences of allopolyploidy may help to explain the phenomenal evolutionary diversification of the silversword alliance.",
keywords = "Inflorescence, MADS-box",
author = "M. Barrier and Baldwin, {B. G.} and Robichaux, {R. H.} and Purugganan, {M. D.}",
year = "1999",
language = "English (US)",
volume = "16",
pages = "1105--1113",
journal = "Molecular Biology and Evolution",
issn = "0737-4038",
publisher = "Oxford University Press",
number = "8",

}

TY - JOUR

T1 - Interspecific hybrid ancestry of a plant adaptive radiation

T2 - Allopolyploidy of the Hawaiian silversword alliance (Asteraceae) inferred from floral homeotic gene duplications

AU - Barrier, M.

AU - Baldwin, B. G.

AU - Robichaux, R. H.

AU - Purugganan, M. D.

PY - 1999

Y1 - 1999

N2 - The polyploid Hawaiian silversword alliance (Asteraceae), a spectacular example of adaptive radiation in plants, was shown previously to have descended from North American tarweeds of the Madia/Raillardiopsis group, a primarily diploid assemblage. The origin of the polyploid condition in the silversword alliance was not resolved in earlier biosystematic, cytogenetic, and molecular studies, apart from the determination that polyploidy in modem species of Madia/Raillardiopsis arose independent of that of the Hawaiian group. We determined that two floral homeotic genes, ASAP3/TM6 and ASAP1, are found in duplicate copies within members of the Hawaiian silversword alliance and appear to have arisen as a result of interspecific hybridization between two North American tarweed species. Our molecular phylogenetic analyses of the ASAP3/TM6 loci suggest that the interspecific hybridization event in the ancestry of the Hawaiian silversword alliance involved members of lineages that include Raillardiopsis muirii (and perhaps Madia nutans) and Raillardiopsis scabrida. The ASAP1 analysis also indicates that the two species of Raillardiopsis are among the closest North American relatives of the Hawaiian silversword alliance. Previous biosystematic evidence demonstrates the potential for allopolyploid formation between members of the two North American tarweed lineages; a vigorous hybrid between R. muirii and R. scabrida has been produced that formed viable, mostly tetraporate (diploid) pollen, in keeping with observed meiotic failure. Various genetic consequences of allopolyploidy may help to explain the phenomenal evolutionary diversification of the silversword alliance.

AB - The polyploid Hawaiian silversword alliance (Asteraceae), a spectacular example of adaptive radiation in plants, was shown previously to have descended from North American tarweeds of the Madia/Raillardiopsis group, a primarily diploid assemblage. The origin of the polyploid condition in the silversword alliance was not resolved in earlier biosystematic, cytogenetic, and molecular studies, apart from the determination that polyploidy in modem species of Madia/Raillardiopsis arose independent of that of the Hawaiian group. We determined that two floral homeotic genes, ASAP3/TM6 and ASAP1, are found in duplicate copies within members of the Hawaiian silversword alliance and appear to have arisen as a result of interspecific hybridization between two North American tarweed species. Our molecular phylogenetic analyses of the ASAP3/TM6 loci suggest that the interspecific hybridization event in the ancestry of the Hawaiian silversword alliance involved members of lineages that include Raillardiopsis muirii (and perhaps Madia nutans) and Raillardiopsis scabrida. The ASAP1 analysis also indicates that the two species of Raillardiopsis are among the closest North American relatives of the Hawaiian silversword alliance. Previous biosystematic evidence demonstrates the potential for allopolyploid formation between members of the two North American tarweed lineages; a vigorous hybrid between R. muirii and R. scabrida has been produced that formed viable, mostly tetraporate (diploid) pollen, in keeping with observed meiotic failure. Various genetic consequences of allopolyploidy may help to explain the phenomenal evolutionary diversification of the silversword alliance.

KW - Inflorescence

KW - MADS-box

UR - http://www.scopus.com/inward/record.url?scp=0032766676&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0032766676&partnerID=8YFLogxK

M3 - Article

C2 - 10474905

AN - SCOPUS:0032766676

VL - 16

SP - 1105

EP - 1113

JO - Molecular Biology and Evolution

JF - Molecular Biology and Evolution

SN - 0737-4038

IS - 8

ER -