TY - JOUR T1 - Serum levels of L1-ORF1p and airflow limitation JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00247-2018 VL - 5 IS - 4 SP - 00247-2018 AU - Stefano Guerra AU - Monica M. Vasquez AU - Pasano Bojang, Jr AU - Irma N. Ramos AU - Duane L. Sherrill AU - Fernando D. Martinez AU - Marilyn Halonen AU - Kenneth S. Ramos Y1 - 2019/10/01 UR - http://openres.ersjournals.com/content/5/4/00247-2018.abstract N2 - LINE-1 (long interspersed nuclear element-1) is a group of polymorphic DNA sequences in the human genome that mobilise via RNA binding proteins, reverse transcriptase and endonuclease to alter the host genome via mutational insertions, chromosomal rearrangements and reprogramming of gene expression (reviewed by Ramos et al. [1]). Full-length LINE-1 sequences encode two proteins: L1-ORF1p, a 40-kDa protein with nucleic acid binding activity; and L1-ORF2p, a 150-kDa protein with endonuclease and reverse transcriptase activities. The activity of LINE-1 is repressed in somatic tissues via DNA methylation and covalent protein modifications, and reactivated by displacement of retinoblastoma-associated proteins from the regulatory region [2]. Recent studies in our laboratory have implicated LINE-1 as a master regulator of human bronchial epithelial cell phenotypes in experimental in vitro and in vivo models [3].In a population-based study, higher circulating levels of L1-ORF1p were associated with lower lung function levels and increased risk for airflow limitation among former smokers http://bit.ly/2ZEIjNv ER -