Using a monoclonal antibody (MAb1.1ASML) raised against a surface glycoprotein of the metastasizing rat pancreatic carcinoma cell line BSp73ASML, cDNA clones have been isolated that encode glycoproteins with partial homology to CD44, a presumed adhesion molecule. In one of the clones, pMeta-1, the epitope marks an additional extracellular domain of 162 amino acids inserted into the rat CD44 protein between amino acid positions 223 and 247 (by analogy to human and murine CD44). The new variants are expressed only in the metastasizing cell lines of two rat tumors, the pancreatic carcinoma BSp73 and the mammary adenocarcinoma 13762NF; they are not expressed in the non-metastasizing tumor cell lines nor in most normal rat tissues. Overexpression of pMeta-1 in the nonmetastasizing BSp73AS cells suffices to establish full metastatic behavior.

(2016) m6A potentiates Sxl alternative pre-mRNA splicing for robust Drosophila sex determination. Nature, 540 (7632). pp. 301-304. ISSN 1476-4687 Access from the University of Nottingham repository: http://eprints.nottingham.ac.uk/39448/1/Nature_m6A_2016.pdf Copyright and reuse:The Nottingham ePrints service makes this work by researchers of the University of Nottingham available open access under the following conditions. This article is made available under the University of Nottingham End User licence and may be reused according to the conditions of the licence. For more details see: http://eprints.nottingham.ac.uk/end_user_agreement.pdf A note on versions:The version presented here may differ from the published version or from the version of record. If you wish to cite this item you are advised to consult the publisher's version. Please see the repository url above for details on accessing the published version and note that access may require a subscription. sex bias towards maleness. This is because m6A is required for female-specific AS of Sxl, 37 which determines female physiognomy, but also translationally represses male-specific 38 lethal2 (msl-2) to prevent dosage compensation normally occurring in males. We further 39show that the m6A reader protein YT521-B decodes m6A in the sex-specifically spliced 40 intron of Sxl, as its absence phenocopies dIME4 mutants. Loss of m6A also affects AS of 41 additional genes, predominantly in the 5'UTR, and has global impacts on the expression of 42 metabolic genes. Requirement of m6A and its reader YT521-B for female-specific Sxl AS 43 reveal that this hitherto enigmatic mRNA modification constitutes an ancient and specific 44 mechanism to adjust levels of gene expression. 45In mature mRNA the m6A modification is most prevalently found around the stop codon as well 46 as in 5'UTRs and in long exons in mammals, plants and yeast 2,3,6,7,15 . Since methylosome 47 components predominantly localize to the nucleus it has been speculated that m6A localized in 48Haussmann et al.3 pre-mRNA introns could have a role in AS regulation in addition to such a role when present in 49 long exons [9][10][11][12]16 . This prompted us to investigate whether m6A is required for Sxl AS, which 50 determines female sex and prevents dosage compensation in females 13 . We generated a null 51 allele of the Drosophila METTL3 methyltransferase homologue dIME4 by imprecise excision of 52 a P-element inserted in the promoter region. The excision ∆22-3 deletes most of the protein-53 coding region including the catalytic domain and is thus referred to as dIME4 null (Fig 1a). These 54 flies are viable and fertile, but flightless, and this phenotype can be rescued by a genomic 55 construct restoring dIME4 (Fig 1a and b). dIME4 shows increased expression in the brain, and 56 like in mammals and plants 17, localizes to the nucleus (Fig 1c,d). 57Following RNAse T1 digestion and 32 P end-labeling of RNA fragments we detected m6A after G 58 in polyA mRNA of adult flies at relatively low l...

-methyladenosine (mA) is the most abundant mRNA modification in eukaryotes, playing crucial roles in multiple biological processes. mA is catalyzed by the activity of methyltransferase-like 3 (Mettl3), which depends on additional proteins whose precise functions remain poorly understood. Here we identified Zc3h13 (zinc finger CCCH domain-containing protein 13)/Flacc [Fl(2)d-associated complex component] as a novel interactor of mA methyltransferase complex components in and mice. Like other components of this complex, Flacc controls mA levels and is involved in sex determination in We demonstrate that Flacc promotes mA deposition by bridging Fl(2)d to the mRNA-binding factor Nito. Altogether, our work advances the molecular understanding of conservation and regulation of the mA machinery.