Figure 1

In silico examination of the conserved transcription factor binding sites and response elements within five endogenous retrovirus-K (ERVK) 5^′-LTRs using ALGGEN-PROMO software [25]. The ERVK LTR consensus sequence was constructed using individual ERVK LTRs in the following order (GenBank accession numbers in brackets): ERVK-10 (M12854.1), ERVK-9 (former HERV-K109) (AF164615.1), ERVK-8 (former HERV-K115) (AY037929.1), ERVK-6 (former HERV-K108) (AF074086.2) and ERVK-113 (JF742069.1). GC boxes 1 to 4, indicated by asterisks, were adapted from [22]. Abbreviations used include: PRE = Progesterone Response Element, CRE = CREB Response Element, ERE = Estrogen Response Element, ARE = Androgen Response Element, E-box = Enhancer Box, GRE = Glucocorticoid Response Element, ISRE = Interferon-Stimulated Response Element, GC box, GA box, ORE = Oct Response Element. Conventional (793bp) [22] and three alternative (460, 570, and 826 bp) [21, 23] transcriptional start sites are depicted by black and grey arrows, respectively. Sequence alignment and annotation were performed using Geneious software [26].