RT Journal Article SR Electronic T1 Genome-wide characterization of PRE-1 reveals a hidden evolutionary relationship between suidae and primates JF bioRxiv FD Cold Spring Harbor Laboratory SP 025791 DO 10.1101/025791 A1 Hao Yu A1 Qingyan Wu A1 Jing Zhang A1 Ying Zhang A1 Chao Lu A1 Yunyun Cheng A1 Zhihui Zhao A1 Andreas Windemuth A1 Di Liu A1 Linlin Hao YR 2015 UL http://biorxiv.org/content/early/2015/08/31/025791.abstract AB We identified and characterized a free PRE-1 element inserted into the promoter region of the porcine IGFBP7 gene whose integration mechanisms into the genome, including copy number, distribution preferences, capacity to exonize and phyloclustering pattern are similar to that of the primate Alu element. 98% of these PRE-1 elements also contain two conserved internal AluI restriction enzyme recognition sites, and the RNA structure of PRE1 can be folded into a two arms model like the Alu RNA structure. It is more surprising that the length of the PRE-1 fragments is nearly the same in 20 chromosomes and positively correlated to its fracture site frequency. All of these fracture sites are close to the mutation hot spots of PRE-1 families, and most of these hot spots are located in the non-complementary fragile regions of the PRE-1 RNA structure. Sequence homology analysis showed that the PRE-1 element seemed to share a common ancestor 7SL RNA with primates but was generated by different evolutionary model, which suggests that the suidae may be the closest relatives to primates in laurasiatheria.