02359naa a2200301 a 450000100080000000500110000800800410001902400330006010000200009324501460011326000090025952014570026865000150172565000180174065000260175865000230178465000200180765000110182765300200183870000150185870000180187370000180189170000180190970000190192770000130194670000140195977300840197320587502017-06-27       2017    bl uuuu     u00u1 u    #d7 a10.1074/mcp.M116.0634952DOI1 aPINHEIRO, P. V.  aHost plants indirectly influence plant virus transmission by altering gut cysteine protease activity of aphid vectors.h[electronic resource]  c2017  aThe green peach aphid, Myzus persicae, is a vector of the Potato leafroll virus (PLRV, Luteoviridae), transmitted exclusively by aphids in a circulative manner. PLRV transmission efficiency was significantly reduced when a clonal lineage of M. persicae was reared on turnip as compared to the weed physalis, a transient effect caused by a host-switch response. A trend of higher PLRV titer in physalis-reared aphids as compared to turnip-reared aphids was observed at 24h and 72h after virus acquisition. The major difference in the proteomes of these aphids was the upregulation of predicted lysosomal enzymes, in particular the cysteine protease cathepsin B (cathB), in aphids reared on turnip. The aphid midgut is the site of PLRV acquisition, and cathB and PLRV localization were starkly different in midguts of the aphids reared on the two host plants. In viruliferous aphids that were reared on turnip, there is near complete co-localization of cathB and PLRV at the cell membranes, which was not observed in physalis-reared aphids. Chemical inhibition of cathB restored the ability of aphids reared on turnip to transmit PLRV in a dose-dependent manner, showing that the increased activity of cathB and other cysteine proteases at the cell membrane indirectly decreases virus transmission by aphids. Understanding how the host plant influences virus transmission by aphids is critical for growers to manage the spread of virus among field crops.  aAphidoidea  aPlant viruses  aPotato leafroll virus  aVirus transmission  aPraga de planta  aVírus  aHost resistance1 aGHANIM, M.1 aALEXANDER, M.1 aREBELO, A. R.1 aSANTOS, R. S.1 aORSBURN, B. C.1 aGRAY, S.1 aCILIA, M.  tMolecular & Cellular Proteomicsgv. 16, n. 4 suppl. 1, p. S230-S243, Apr. 2017.