PFEIL, BERNARD E.1,2*, C.L. BRUBAKER1, L.A. CRAVEN1, and M.D. CRISP2. 1Centre for Plant Biodiversity Research, CSIRO Plant Industry, GPO Box 1600, Canberra ACT 2601, Australia; 2Australian National University, Division of Botany and Zoology, Canberra ACT 0200, Australia. - Gene duplication, allopolyploidy and pseudogenes: analysis of rpb2 low-copy nDNA sequences in Malvaceae.
The utility of low-copy nuclear sequences from the second-largest
subunit of RNA polymerase II (rpb2) for phylogenetic analysis is
examined in Malvaceae s.s. (Malvoideae), a family which is c. 40
million years old. A c. 700 base pair region which includes three
small introns produced well-supported and well-resolved results
consistent with cpDNA phylogenies for the family. However, this region
is not present as a single copy in this family - it is duplicated in
Hibiscus and several related genera. The phylogenetic inference
from each copy is very similar, although both copies were not
recovered for all taxa sampled. Allopolyploid events were identified
in several lineages within Hibiscus. Two examples of
pseudogenisation were also inferred.
Key words: allopolyploidy, gene duplication, Malvaceae, rpb2