1 Deep transcriptome annotation enables the discovery and functional 2 characterization of cryptic small proteins 3 4 5 Sondos Samandi1,7†, Annie V. Roy1,7†, Vivian Delcourt1,7,8, Jean-François Lucier2, 6 Jules Gagnon2, Maxime C. Beaudoin1,7, Benoît Vanderperre1, Marc-André Breton1, Julie 7 Motard1,7, Jean-François Jacques1,7, Mylène Brunelle1,7, Isabelle Gagnon-Arsenault6,7, 8 Isabelle Fournier8, Aida Ouangraoua3, Darel J. Hunting4, Alan A. Cohen5, Christian R. 9 Landry6,7, Michelle S. Scott1, Xavier Roucou1,7* 10 11 1Department of Biochemistry, 2Department of Biology and Center for Computational 12 Science, 3Department of Computer Science, 4Department of Nuclear Medicine & 13 Radiobiology, 5Department of Family Medicine, Université de Sherbrooke, Québec, 14 Canada; 6Département de biologie, Département de biochimie, microbiologie et bio- 15 informatique and IBIS, Université Laval, Québec, Canada; 7PROTEO, Québec Network 16 for Research on Protein Function, Structure, and Engineering, Québec, Canada; 17 8Université Lille, INSERM U1192, Laboratoire Protéomique, Réponse Inflammatoire & 18 Spectrométrie de Masse (PRISM) F-59000 Lille, France 19 20 †These authors contributed equally to this work 21 *Correspondance to Xavier Roucou: Département de biochimie (Z8-2001), Faculté de 22 Médecine et des Sciences de la Santé, Université de Sherbrooke, 3201 Jean Mignault, 1 23 Sherbrooke, Québec J1E 4K8, Canada, Tel. (819) 821-8000x72240; Fax. (819) 820 6831; 24 E-Mail:
[email protected] 25 26 Abstract 27 28 Recent functional, proteomic and ribosome profiling studies in eukaryotes have 29 concurrently demonstrated the translation of alternative open reading frames (altORFs) in 30 addition to annotated protein coding sequences (CDSs). We show that a large number of 31 small proteins could in fact be coded by these altORFs.