title: The post-apoptotic fate of RNAs identified through high-throughput sequencing of human hair.
abstract: The hair of all mammals consists of terminally differentiated cells that undergo a specialized form of apoptosis called cornification. While DNA is destroyed during cornification, the extent to which RNA is lost is unknown. Here we find that multiple types of RNA are incompletely degraded after hair shaft formation in both mouse and human. Notably, mRNAs and short regulatory microRNAs (miRNAs) are stable in the hair as far as 10 cm from the scalp. To better characterize the post-apoptotic RNAs that escape degradation in the hair, we performed sequencing (RNA-seq) on RNA isolated from hair shafts pooled from several individuals. This hair shaft RNA library, which encompasses different hair types, genders, and populations, revealed 7,193 mRNAs, 449 miRNAs and thousands of unannotated transcripts that remain in the post-apoptotic hair. A comparison of the hair shaft RNA library to that of viable keratinocytes revealed surprisingly similar patterns of gene coverage and indicates that degradation of RNA is highly inefficient during apoptosis of hair lineages. The generation of a hair shaft RNA library could be used as months of accumulated transcriptional history useful for retrospective detection of disease, drug response and environmental exposure.
authors: Stem Cell Program, Division of Dermatology, Department of Medicine, Institute for Genomic Medicine, University of California San Diego, San Diego, California, United States of America.
authors: Gloria K
authors: GK
authors: Lefkowitz
authors: Anandaroop
authors: A
authors: Mukhopadhyay
authors: Christopher
authors: C
authors: Cowing-Zitron
authors: Benjamin D
authors: BD
authors: Yu
mesh_terms: D000328:Adult; D000818:Animals; D017209:Apoptosis; D002454:Cell Differentiation; D002470:Cell Survival; D005260:Female; D015723:Gene Library; D006197:Hair / Q000166:cytology / Q000378:metabolism*; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000378:metabolism; D008297:Male; D051379:Mice; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics*; D020871:RNA Stability; D012333:RNA, Messenger / Q000737:chemistry / Q000235:genetics; D017423:Sequence Analysis, RNA / Q000379:methods*; D055815:Young Adult
chemical_list: D035683:MicroRNAs; D012333:RNA, Messenger