Element:Sushi-ichi

Description Sushi-ichi is a LTR retrotransposon characterized in Takifugu rubripes (Poulter and Butler 1998; Butler et al. 2001; Volff et al. 2003). Sushi belongs to V-clade (Llorens et al. 2009) the chromovirus lineage of vertebrate-like Ty3/Gypsy LTR retrotransposons (Marín and Lloréns 2000) characterized by encoding for chromodomain-integrases (Malik and Eickbush 1999). The chromovirus branch has been disclosed to be the most ancient phylogenetic pattern of Ty3/Gypsy retroelements (Gorinsek, Gubensek and Kordis 2004; 2005; Kordis 2005). Sushi has several subtypes. Sushi-ichi is taken as representative. Its genome is 5.6 Kb in size, including LTRs of 560 nt. The internal region of this element displays a Primer Binding Site (PBS), two Open Reading Frames (ORFs) for gag, and pol genes, and a Polypurine Tract (PPT) adjacent to the 3´LTR (Poulter and Butler 1998; Butler et al. 2001; Volff et al. 2003). This element presents a detectable chromodomain at the C-terminal end of the integrase pol polyprotein domain. The PBS of fungi and vertebrate chromoviruses, differs significantly from that used by plant chromoviruses. While plant chromoviruses use a methionine starting tRNA (iMet), fungi and vertebrate chromoviruses use their own self-priming mechanism to start the reverse transcription (Levin 1995 ; Butler et al. 2001). Structure Figure not to scale. If present, long terminal repeats (LTRs) have been highlighted in blue. Amino acid motifs noted with lines indicate the conserved residues in each protein domain, abbreviations below mean: MA=matrix PR=protease DU or DUT=dUTPase TM=transmembrane TAV or IBMP=transactivator/viroplasmin or inclusion body matrix protein CA=capsid RT=reverse transcriptase INT=Integrase CHR=chromodomain NC=nucleocapsid RH=RNaseH SU=surface MOV=movement protein PPT=polypurine tract PBS=primer binding site ATF=aphid transmission factor VAP=virion associated protein Related literature Mobile DNA II. (Craig et al. 2002)

Genbank accession: AF030881 Clade: V-clade Cluster or genus: Fungi and vertebrates Branch or class: Chromoviruses Family: Ty3/Gypsy System: LTR retroelements Host: Explore the Tree Life Project Takifugu rubripes Image, Wikipedia Browse all elements