h-TBP: an approach based on intron-length polymorphism for the rapid isolation and characterization of the multiple members of the b-tubulin gene family in Camelina sativa (L.) Crantz Incoronata Galasso • Antonella Manca • Luca Braglia • Tommaso Martinelli • Laura Morello • Diego Breviario Received: 25 May 2010 / Accepted: 22 September 2010 / Published online: 12 October 2010 Ó Springer Science+Business Media B.V. 2010 Abstract We have developed a new version of the cTBP (combinatorial tubulin-based polymorphism) method, a previously described approach based on intron-length polymorphism (ILP), to rapidly characterize the b-tubulin gene family of Camelina sativa (L.) Crantz, a plant species of importance for oil production but still largely unexplored at genomic level. The method, named h-TBP, allows the rapid cloning of the b-tubulin genomic sequences that encompass the two introns, invariantly present at fixed positions within the coding region of the vast majority of the plant species. The b-tubulin sequences cloned by h-TBP also comprise part of exon1 and exon3 and the whole sequence of exon2. The h-TBP method has then been used to isolate, clone and characterize the b-tubulin gene family of C. sativa, composed of at least 20 different b-tubulin isotypes, named CsTUB1 through CsTUB20. The relatively high number of b-tubulin genes has been further substantiated by Southern-blot analysis. Com- parison of the b-tubulin exon sequences of C. sativa with those of Arabidopsis thaliana, the closest relative among crucifers, defines distinct groups of putative orthologous genes, identified by a UPMGA cluster analysis. Analysis of the C. sativa b-tubulin intron sequences reveals some molecular features that can provide the first hints for the understanding of intron plasticity and evolution. From a more immediate perspective, these data provide the first substantial contribution to the characterization of the largely unexplored genome of C. sativa, and the tools for assisting programmes of breeding and selection of the most productive plants. Keywords ILP  b-tubulin  Introns  Oilseed plant  False flax  Brassicaceae Introduction Camelina sativa (L.) Crantz or false flax, a member of the mustard family (Brassicaceae), is an oilseed plant native to Central Asia and the Mediterranean with both winter and spring annual biotypes. Came- lina is an ancient crop plant used extensively in the past for cooking, cosmetics and as a lamp oil (Knorzer 1978). Camelina cultivation subsequently declined due to low yield when compared to other oilseed crops such as rapeseed or sunflower. Recently, C. sativa has attracted renewed attention as an alternative oilseed plant for biofuel transfor- mation because of its low input requirements such as fertilizers, pesticides and energy (Putnam et al. 1993; Electronic supplementary material The online version of this article (doi:10.1007/s11032-010-9515-0) contains supplementary material, which is available to authorized users. I. Galasso  A. Manca  L. Braglia  T. Martinelli  L. Morello  D. Breviario (&) Istituto di Biologia e Biotecnologia Agraria (IBBA-CNR), via Bassini, 15, 20133 Milan, Italy e-mail: terenzio@ibba.cnr.it 123 Mol Breeding (2011) 28:635–645 DOI 10.1007/s11032-010-9515-0