Abstract Detail

Developmental and Structural Section

Meyer, Rachel [1], Pabon Mora, Natalia [2], Mohamed, Abeer [3], Nowogrodzki, Anna [4], Litt, Amy [4].

Analysis of candidate genes implicated in specifying dry versus fleshy fruit development in the Solanaceae.

The Solanaceae are characterized by a diversity of fruit types, but most species produce either a dry capsule (i.e. Nicotiana sylvestris) or a berry (i.e. Solanum lycopersicum). Phylogenetic reconstruction suggests that the capsule is the ancestral fruit type in the family; concurrent with the origin of the species-rich Solanoideae clade was a dramatic shift to berry formation. The goal of this project is to identify some of the key genetic differences that determine whether a Solanaceae fruit will be dry or fleshy. Using standard histological techniques and in situ hybridization, we have previously identified four comparable landmark stages in the development of the fruit of S. lycopersicum and N. sylvestris. Identification of these stages provides a foundation for comparative transcriptome analyses, with the aim of identifying genes that show differential activity during the development of the two fruit types, and that may play a role in determining the specific traits that characterize dry and fleshy fruits. We have implemented both microarray and next-generation sequencing strategies to identify genes that are expressed differentially between the two species and across the four developmental stages. Our preliminary analysis of genes that are upregulated in each species at the time of fertilization and the concurrent onset of rapid cell division (Stage 2) identified several transcription factors, signalling factors, and genes involved in relevant processes such as cell wall expansion or lignification as being differentially regulated. We have selected 12 such genes for further analysis. RT-PCR and quantitative real-time PCR suggest that some of these genes are broadly expressed in all tissues, with no fruit-specific activity. One of the genes is fruit specific only in N. sylvestris, and others show dynamic patterns of expression suggesting important roles at different developmental stages. We are currently evaluating additional sequence data and selecting genes for functional analyses.

Broader Impacts:

1 - City University of New York, Graduate Center / New York Botanical Gard, Biology, 365 Fifth Avenue, New York, NY, 10016, USA
2 - Graduate Center CUNY/ New York Botanical Garden, Plant Sciences, 200th St and Southern Blvd, Plant Research Laboratory, Bronx, NY, 10458, USA
3 - The New York Botanical Garden, 200th St and Southern Blvd, Bronx, NY, 10458, USA
4 - The New York Botanical Garden, 200th St and Southern Boulevard, Bronx, NY, 10458-5126, USA

Keywords:
Solanaceae
Fruit development
molecular regulation.

Presentation Type: Oral Paper:Papers for Sections
Session: 29
Location: 551A/Convention Center
Date: Tuesday, August 3rd, 2010
Time: 8:45 AM
Number: 29003
Abstract ID:197