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. P. De-ac02-06na25396 and . Tricornutum, Funding for this work was also obtained from the EU-funded FP6 Diatomics project (LSHG-CT-2004-512035), the EU-FP6 Marine Genomics Network of Excellence (GOCE-CT-2004-505403), an ATIP 'Blanche' grant from the CNRS (France) and the Agence Nationale de la Recherche (France), We are grateful to M. Muffato and H.-R. Crollius for the analysis reported in Supplementary Fig. 3a

, Author Contributions C.B. coordinated Phaeodactylum genome annotation and manuscript preparation. E.V.A. coordinated Thalassiosira genome annotation

D. S. , I. V. , J. J. Genoscope, J. H. , J. G. et al., made equivalent and substantial contributions to the data presented, and should be considered joint second authors

, Genome assemblies together with predicted gene models and annotations have been deposited at DDBJ, EMBL and GenBank under the project accessions ABQD00000000 and AAFD00000000, respectively. The versions described in this paper are the first version, ABQD01000000, for P. tricornutum, which includes complete chromosomes 3 and 11 (CP001142 and CP001141), and the second version, AAFD02000000, for T. pseudonana, also including complete chromosomes 7 and 18 (CP001160 and CP001159). P. tricornutum EST expression profiles can be, Author Information Assemblies and annotations of the P. tricornutum and T. pseudonana genomes are available through the JGI Genome Portal at