Gene duplication and polyploidization are genetic mechanisms that instantly add genetic material to an organism's genome. Subsequent modification of the duplicated material leads to the evolution of neofunctionalization (new genetic functions), subfunctionalization (differential retention of genetic functions), redundancy, or a decay of duplicated genes to pseudogenes. Phytochromes are light receptors that play a large role in plant development. They are encoded by a small gene family that in tomato is comprised of five members:
The evolution of floral morphology in the monocot order Zingiberales shows a trend in which androecial whorl organs are progressively modified into variously conspicuous “petaloid” structures with differing degrees of fertility. Petaloidy of androecial members results from extensive laminarization of an otherwise radially symmetric structure. The genetic basis of the laminarization of androecial members has been addressed through recent candidate gene studies focused on understanding the spatiotemporal expression patterns of genes known to be necessary to floral organ formation. Here, we explore the correlation between gene duplication events and floral and inflorescence morphological diversification across the Zingiberales by inferring ancestral character states and gene copy number using the most widely accepted phylogenetic hypotheses. Our results suggest that the duplication and differential loss of
- PAR ID:
- 10031101
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Experimental Zoology Part B: Molecular and Developmental Evolution
- Volume:
- 328
- Issue:
- 1-2
- ISSN:
- 1552-5007
- Page Range / eLocation ID:
- p. 41-54
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract PHYA, PHYB1, PHYB2, PHYE, andPHYF. The most recent gene duplication within this family was in the ancestralPHYB gene. Using transcriptome profiling, co‐expression network analysis, and physiological and molecular experimentation, we show that tomatoSlPHYB1 andSlPHYB2 exhibit both common and non‐redundant functions. Specifically,PHYB1 appears to be the major integrator of light and auxin responses, such as gravitropism and phototropism, whilePHYB1 andPHYB2 regulate aspects of photosynthesis antagonistically to each other, suggesting that the genes have subfunctionalized since their duplication. -
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