Element:Micropia

Description Micropia is a LTR retrotransposon first described as a transcript expressed by fertility genes of chromosome Y of primary spermatocytes of Drosophila hydei (Henning et al. 1983; Huijser et al. 1988). Later, this element was also described in Drosophila melanogaster as a LTR retrotransposon combining structural features of DNA viruses, retroviruses and non-viral transposable elements (Lankenau et al. 1988). Micropia belongs to Micropia/mdg3 clade (Malik and Eickbush 1999). Micropia has several subtypes, the clone Dm11 of D. melanogaster is taken as a representative. The genomic structure of this clone is 5.5 Kb in size including LTRs of 480 nt. The internal region displays a Primer Binding Site (PBS) complementary to a tRNALeu, a single Open Reading Frame (ORF), which codifies for a gag-pol polyprotein, and a Polypurine Tract (PPT) adjacent to the 3´LTRs. Micropia also has a region of similarity to the class I major histocompatibility complex of mammals (Lankenau et al. 1988). This element also encodes an antisense RNA complementary to the Reverse Transcriptase_RNaseH region that seems to be involved in the control expression of transposon-encoded proteins in germ lines (Lankenau, Corces and Lankenau 1994). 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: X14037 Clade: Micropia/Mdg3 Cluster or genus: Undetermined Branch or class: Branch 2 Family: Ty3/Gypsy System: LTR retroelements Host: Explore the Tree Life Project Drosophila melanogaster Image, courtesy of Andreas Trepte, Max-Planck Institute for Molecular Genetics Browse all elements