Richardson Annette C, Rassam Maysoon, McNeilage Mark A, Nain Bhawana, MacDiarmid Robin M, Lo Kim R, Klages Karin, Janssen Bart J, Hellens Roger P, Gera Emma, Fraser Lena G, Ferguson A Ross, Eckloff Rheinhart, Davy Marcus W, Bowen Judith H, Boldingh Helen L, Allan Andrew C, Usadel Björn, Schaffer Robert J, Newcomb Richard D, Montefiori Mirco, Matich Adam J, Marsh Ken B, Chagne David, Bulley Sean M, Beuning Lesley L, Atkinson Ross G, Ampomah-Dwamena Charles, MacRae Elspeth A, Gleave Andrew P, Crowhurst Ross N, Rikkerink Erik HA, Ross Gavin S, Schröder Roswitha, Snowden Kimberley C, Souleyre Edwige JF, Templeton Matt D, Walton Eric F, Wang Daisy, Wang Mindy Y, Wang Yanming Y, Wood Marion, Wu Rongmei, Yauk Yar-Khing, and Laing William A
Abstract Background Kiwifruit (Actinidia spp.) are a relatively new, but economically important crop grown in many different parts of the world. Commercial success is driven by the development of new cultivars with novel consumer traits including flavor, appearance, healthful components and convenience. To increase our understanding of the genetic diversity and gene-based control of these key traits in Actinidia, we have produced a collection of 132,577 expressed sequence tags (ESTs). Results The ESTs were derived mainly from four Actinidia species (A. chinensis, A. deliciosa, A. arguta and A. eriantha) and fell into 41,858 non redundant clusters (18,070 tentative consensus sequences and 23,788 EST singletons). Analysis of flavor and fragrance-related gene families (acyltransferases and carboxylesterases) and pathways (terpenoid biosynthesis) is presented in comparison with a chemical analysis of the compounds present in Actinidia including esters, acids, alcohols and terpenes. ESTs are identified for most genes in color pathways controlling chlorophyll degradation and carotenoid biosynthesis. In the health area, data are presented on the ESTs involved in ascorbic acid and quinic acid biosynthesis showing not only that genes for many of the steps in these pathways are represented in the database, but that genes encoding some critical steps are absent. In the convenience area, genes related to different stages of fruit softening are identified. Conclusion This large EST resource will allow researchers to undertake the tremendous challenge of understanding the molecular basis of genetic diversity in the Actinidia genus as well as provide an EST resource for comparative fruit genomics. The various bioinformatics analyses we have undertaken demonstrates the extent of coverage of ESTs for genes encoding different biochemical pathways in Actinidia.