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Romero, A.

Publications and source records attributed to Romero, A..

3 recordsLinked to original sources

Pathogenic mycobacteria manipulate host low density lipoprotein metabolism

Changes to lipid metabolism are well-characterised consequences of human tuberculosis infection but their functional relevance are not clearly elucidated in these or other host-mycobacterial systems. The zebrafish-Mycobacterium marinum infection model is used extensively to model many aspects of human-M. tuberculosis pathogenesis but has not been widely used to study the role of infection-induced lipid metabolism. We find mammalian mycobacterial infection-induced alterations in host Low Density Lipoprotein metabolism are conserved in the zebrafish model of mycobacterial pathogenesis. Depletion of LDLR, a key lipid metabolism node, decreased M. marinum burden, and corrected infection-induced altered lipid metabolism resulting in decreased LDL and reduced the rate of macrophage transformation into foam cells. Our results demonstrate a conserved role for infection-induced alterations to host lipid metabolism, and specifically the LDL-LDLR axis, across host-mycobacterial species pairings.\n\nFundingThis work was supported by the Australian National Health and Medical Research Council (APP1099912 and APP1053407 to S.H.O.); Meat and Livestock Australia (P.PSH. 0813 to A.C.P. and K. dS); the Marie Bashir Institute for Infectious Diseases and Biosecurity (grant to S.H.O., A.C.P. and K. dS); the Kenyon Family Foundation Inflammation Award (grant to S.H.O.); the University of Sydney (fellowship to S.H.O.); Conselleria de Economia, Emprego e Industria (GAIN), Xunta de Galicia (grant IN607B 2016/12 to Institute of Marine Research (IIM-CSIC)).

immunology

Genomic insights into the domestication of the chocolate tree, Theobroma cacao L.

Domestication has had a strong impact on the development of modern societies. We sequenced 200 genomes of the chocolate plant Theobroma cacao L. to show for the first time that a single population underwent strong domestication approximately 3,600 years (95% CI: 2481 - 10,903 years ago) ago, the Criollo population. We also show that during the process of domestication, there was strong selection for genes involved in the metabolism of the colored protectants anthocyanins and the stimulant theobromine, as well as disease resistance genes. Our analyses show that domesticated populations of T. cacao (Criollo) maintain a higher proportion of high frequency deleterious mutations. We also show for the first time the negative consequences the increase accumulation of deleterious mutations during domestication on the fitness of individuals (significant negative correlation between Criollo ancestry and Kg of beans per hectare per year, P = 0.000425).

genomics

The microprotein Minion controls cell fusion and muscle formation

Although recent evidence has pointed to the existence of small open reading frame (smORF)-encoded microproteins in mammals, the functional repertoire of this microproteome remains to be determined1. In skeletal muscle, proper development requires fusion of mononuclear progenitors to form multinucleated myotubes, a critical but poorly understood process2,3. Here we report the identification of a small ORF encoding an essential skeletal muscle specific microprotein we term Minion (microprotein inducer of fusion). Myogenic progenitors lacking Minion differentiate normally but fail to form syncytial myotubes, and Minion-deficient mice die perinatally with marked reduction in fused muscle fibers. This fusogenic activity is conserved to the human Minion ortholog, previously annotated as a long noncoding RNA. Loss-of-function studies demonstrate that Minion is the factor providing muscle specific fusogenic function for the transmembrane protein Myomaker4. Remarkably, we demonstrate that co-expression of Minion and Myomaker is sufficient to induce rapid cytoskeletal rearrangement and homogeneous cellular fusion, even in non-muscle cells. These findings establish Minion as a novel microprotein required for muscle development, and define a two-component program for the induction of mammalian cell fusion, enabling both research and translational applications. Importantly, these data also significantly expand the known functions of smORF-encoded microproteins, an under-explored source of proteomic diversity.

cell biology