An acorn squash (Cucurbita pepo ssp. ovifera) fruit and seed transcriptome as a resource for the study of fruit traits in Cucurbita. (28th January 2015)

• Record Type: Journal Article
• Authors: Wyatt, Lindsay E; Strickler, Susan R; Mueller, Lukas A; Mazourek, Michael
• Is Part Of: Horticulture research. Volume 2(2015)
• Publication Date: 2015-01-28
• Subjects: Plant genetics -- Plant molecular biology; Horticulture -- Research -- Periodicals; 635.072
• DOI: 10.1038/hortres.2014.70
• Languages: English
• ISSNs: 2052-7276

Abstract

Abstract: Acorn squash ( Cucurbita pepo ) is an iconic fall vegetable in the United States, known for its unique fruit shape and also prized for its culinary properties. Little is known about the metabolism that underlies the development of fruit quality attributes such as color, sweetness, texture and nutritional qualities in acorn squash, or any other winter squash grown worldwide. To provide insight into winter squash fruit and seed development and add to the genomic resources in the Cucurbita genus, RNA sequencing was used to generate an acorn squash fruit and seed transcriptome from the cultivar Sweet REBA at critical points throughout fruit development. 141 838 600 high-quality paired-end Illumina reads were assembled into 55 949 unigenes. 85% of unigenes with predicted open reading frames had homology with previously identified genes and over 62% could be functionally annotated. Comparison with the watermelon and cucumber genomes provided confirmation that the unigenes are full-length and comprehensive, covering an average of 90% of the coding sequence of their homologs and 72% of the cucumber and watermelon exomes. Key candidate genes associated with carotenoid and carbohydrate metabolism were identified toward a resource for winter squash fruit quality trait dissection. This transcriptome represents a major advance in C. pepo genomics, providing significant new sequence information and revealing the repertoire of genes expressed throughout winter squash fruit and seed development. Future studies on the genetic basis of fruit quality and future breeding efforts will be enhanced by tools and insights developed from this resource. Abstract : Genomics: Insights into squash fruit development An analysis of genes active in developing fruit provides a resource for breeding better quality squashes. Acorn squash ( Cucurbita pepo ) fruit is prized for their color and nutritional value. Previously, the only genomic information for C. pepo was derived from vegetative and floral tissues. Now, Michael Mazourek and colleagues, at Cornell University and the Boyce Thompson Institute for Plant Research, USA, used RNA sequencing to indicate the full set of active genes in developing acorn squash fruit. This 'transcriptome' indicates almost 56, 000 genes, over 8, 000 unique to the fruit. Among these, the researchers identified genes associated with carotenoid and carbohydrate metabolism, which affect nutrient content, flavor and texture. This may facilitate breeding more nutritious and better-storing varieties. The transcriptome provides a valuable resource for research across Cucurbita, which also includes zucchini and pumpkin.