Background with Pat!
- Error fetching PMID 11092833:
More population genetics of polyploidy!
I did a literature search today and found several interesting papers. I picked two for next week, but in the interest of time, I think we should focus on the first one (Walsh paper). The Comai paper can be background reading for people who want to do a little polyploidy catch-up (like me). Both Genetica and Nature Reviews Genetics are available online through the library.
- Error fetching PMID 12868616:
- Error fetching PMID 16304599:
Ploidy shifts with Pat and Brian.
The yeast haploid superiority article (Zeyl, 2003, Science below) dovetails nicely with the Walsh reading from April 17 and the Otto review from April 10.
A recent paper on gene duplicate evolution in Teleost fish should further expand on experimental observations related to evolution specific to polyploid contexts.
- Error fetching PMID 12543972:
- Error fetching PMID 16809621:
Speciation with Dena
Great paper from the Solti, Pires, and Leitch groups from a meeting proceedings at Kew Gardens. Demonstrates that in this case the species barrier was not overcome just once in a freak accident.
Polyploid tree frogs unite to form a complex interspecies swarm. Demonstrates recurrent polyploid formation can play a role in animal polyploid speciation too. Go frogs.
Contemporary polyploidy hybrids with Debra Ayers
Abbott and Lowe paper on Senecios (HTML): http://www.blackwell-synergy.com/doi/full/10.1111/j.1095-8312.2004.00333.x
Urbanska paper on Cardamine: http://springerlink.metapress.com/content/g6977375111059p4/fulltext.pdf
Plus unpublished nuggets on local spartina and tumbleweeds!
The triploid bridge with Brian
With so much new stuff to be discovered (mathematical models of polyploid establishment under mixed asexual/sexual breeding schemes) I decided to settle on some steady material.
- For a review on the origins of polyploids I offer up the first (of two) reviews by Justin Ramsey and Doug Schemske (1998, or here). The sections about triploids and the triploid bridge are all I think we should focus on. There is a lot of meat in this review.
- The second is a paper by Brian Husband that looks at the effect of triploid fitness on the evolution of polyploidy in populations.
- Last is a paper from the Comai group looking at the existence of variability in both triploid and aneuploid fitness. There is a methods paper in the plant journal (Henry 2006) and a previous paper in Genetics (Henry et al., 2005) that mirrors some of the figures presented in Ramsey and Schemske for maize (or Satina and Blakeslee 1936/37 for Datura).
The triploid bridge is not just for evolution. It gets used by breeders ocassionally, and talked about often. I have linked a paper by Carputo et al. on the uses and usefulness of the "EBN", one of which is to make odd-ploidy hybrids as a bridge to allow gene flow between isolated species. I don't think there will be time to discuss it.
Polyploidy in Animals
The time has to come to put on our zoology glasses and examine polyploidy in animal species. I've picked two papers, one of which was on the initial "suggested readings list" passed out at the beginning of class.
Mable, B. K. 2004. 'Why polyploidy is rare in animals than in plants': myths and mechanisms. Biological Journal of the Linnean Society 82:453-466 (http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1095-8312.2004.00332.x). If people are interested, they can read the original paper "Why polyploidy is rarer in animals than in plants revisited" (Orr 1990; although if it is being revisited, there must be an older paper with a similar title).
Le Comber, S. C. and C. Smith. 2004. Polyploidy in fishes: patterns and processes. Biological Journal of the Linnean Society 82:431-422 (http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1095-8312.2004.00330.x.)