Molecular evolution of HoxA13 and the multiple origins of limbless morphologies in amphibians and reptiles

Abstract Despite the importance of polyploidy in the evolution of plants, patterns of molecular evolution and genomic interactions following polyploidy are not well understood. Nuclear ribosomal DNA is particularly complex with respect to these genomic interactions. The composition of nrDNA tandem arrays is influenced by intra- and interlocus concerted evolution and their expression is characterized by patterns such as nucleolar dominance. To understand these complex interactions it is important to study them in diverse natural polyploid systems. In this study we use direct sequencing to isolate and characterize nrDNA internal transcribed spacer (ITS) homeologues from multiple accessions of six different races in the Glycine tomentella allopolyploid complex. The results indicate that in most allopolyploid accessions both homeologous nrDNA repeats are present, but that there are significant biases in copy number toward one homeologue, possibly resulting from interlocus concerted evolution. The predominant homeologue often differs between races and between accessions within a race. A phylogenetic analysis of ITS sequences provides evidence for multiple origins in several of the polyploid races. This evidence for diverse patterns of nrDNA molecular evolution and multiple origins of polyploid races will provide a useful system for future studies of natural variation in patterns of nrDNA expression.

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Molecular Evolution of Aldolase A Pseudogenes in Mice: Multiple Origins, Subsequent Duplications, and Heterogeneity of Evolutionary Rates

Molecular Biology and Evolution ◽

10.1093/oxfordjournals.molbev.a003953 ◽

2001 ◽

Vol 18 (9) ◽

pp. 1643-1653 ◽

Cited By ~ 1

Author(s):

María Noel Cortinas ◽

Enrique P. Lessa

Keyword(s):

Molecular Evolution ◽

Evolutionary Rates ◽

Multiple Origins ◽

Aldolase A

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Molecular evolution of a cytochrome P450 for the synthesis of potential antidepressant (2R,6R)-hydroxynorketamine

Chemical Communications ◽

10.1039/d0cc06729f ◽

2021 ◽

Author(s):

Ansgar Bokel ◽

Michael C. Hutter ◽

Vlada B. Urlacher

Keyword(s):

Cytochrome P450 ◽

Molecular Evolution ◽

Cytochrome P450 Monooxygenase ◽

P450 Monooxygenase ◽

Effective Synthesis

Engineered cytochrome P450 monooxygenase CYP154E1 enables the effective synthesis of the potential antidepressant (2R,6R)-hydroxynorketamine via N-demethylation and regio- and stereoselective hydroxylation of (R)-ketamine.

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The Neutral Theory of Molecular Evolution

10.1017/cbo9780511623486 ◽

1983 ◽

Cited By ~ 4273

Author(s):

Motoo Kimura

Keyword(s):

Molecular Evolution ◽

Neutral Theory

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Molecular Evolution: Producing the Biochemical Data

10.1016/s0076-6879(00)x0406-5 ◽

2005 ◽

Keyword(s):

Molecular Evolution ◽

Biochemical Data

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Molecular evolution of n-formyl peptide and C5a receptors in non-human primates

Immunology Letters ◽

10.1016/s0165-2478(97)87276-8 ◽

1997 ◽

Vol 56 (1-3) ◽

pp. 110

Author(s):

S Gonzalez

Keyword(s):

Molecular Evolution ◽

C5a Receptors ◽

Formyl Peptide

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Comparative Analysis of Genetic and Morphological Variation within the Platanthera hyperborea Complex (Orchidaceae)

Systematic Botany ◽

10.1600/036364420x16033962925303 ◽

2020 ◽

Vol 45 (4) ◽

pp. 767-778

Author(s):

Eranga Wettewa ◽

Nick Bailey ◽

Lisa E. Wallace

Keyword(s):

North America ◽

Diploid Species ◽

Morphological Characters ◽

Evolutionary Patterns ◽

Founding Population ◽

Multiple Origins ◽

Geographic Structure ◽

Species Complexes ◽

Nuclear Its ◽

Cryptic Taxa

Abstract—Species complexes present considerable problems for a working taxonomy due to the presence of intraspecific variation, hybridization, polyploidy, and phenotypic plasticity. Understanding evolutionary patterns using molecular markers can allow for a more thorough assessment of evolutionary lineages than traditional morphological markers. In this study, we evaluated genetic diversity and phylogenetic patterns among taxa of the Platanthera hyperborea (Orchidaceae) complex, which includes diploid (Platanthera aquilonis) and polyploid (Platanthera hyperborea, P. huronensis, and P. convallariifolia) taxa spanning North America, Greenland, Iceland, and Asia. We found that three floral morphological characters overlap among the polyploid taxa, but the diploid species has smaller flowers. DNA sequence variation in a plastid (rpL16 intron) and a nuclear (ITS) marker indicated that at least three diploid species have contributed to the genomes of the polyploid taxa, suggesting all are of allopolyploid origin. Platanthera convallariifolia is most like P. dilatata and P. stricta, whereas P. huronensis and P. hyperborea appear to have originated from crosses of P. dilatata and P. aquilonis. Platanthera huronensis, which is found across North America, has multiple origins and reciprocal maternal parentage from the diploid species. By contrast, P. hyperborea, restricted to Greenland and Iceland, appears to have originated from a small founding population of hybrids in which P. dilatata was the maternal parent. Geographic structure was found among polyploid forms in North America. The area of Manitoba, Canada appears to be a contact zone among geographically diverse forms from eastern and western North America. Given the geographic and genetic variation found, we recommend continued recognition of four green-flowered species within this complex, but caution that there may be additional cryptic taxa within North America.

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