Element:Osser

Description Osser is the first complete algae Ty1/Copia-like retroelement described in the green alga Volvox carteri (Lindauer et al. 1993). Osser constitutes a one-single-sequence clade within Branch 2 of the Ty1/Copia LTR retrotransposons family (Llorens et al. 2009) as it has no phylogenetic relatives to date reported. The full-length Osser genome is 4885 bp in size, including two identical 197-bp LTRs. The internal region of this element presents a Primer Binding Site (PBS) for a tRNAMet, two overlapping Open Reading Frames (ORFs) containing the typical gag and pol domains of Ty1/Copia LTR retrotransposons: gag (in which is present the zinc finger motif of Cys-His type characteristic of the nucleocapside domain), protease, integrase, reverse transcriptase and ribonuclease H; and a Polypurine Tract (PPT) upstream its 3’ LTR (Lindauer et al. 1993). 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: 288596 Clade: Osser Cluster or genus: Undetermined Branch or class: Branch 2 Family: Ty1/Copia System: LTR retroelements Host: Explore the Tree Life Project Volvox carteri Carol Ann Borden, Department of Botany, University of British Columbia Browse all elements