title: TALE: a tale of genome editing.
abstract: Transcription activator-like effectors (TALEs), first identified in Xanthomonas bacteria, are naturally occurring or artificially designed proteins that modulate gene transcription. These proteins recognize and bind DNA sequences based on a variable numbers of tandem repeats. Each repeat is comprised of a set of ∼ 34 conserved amino acids; within this conserved domain, there are usually two amino acids that distinguish one TALE from another. Interestingly, TALEs have revealed a simple cipher for the one-to-one recognition of proteins for DNA bases. Synthetic TALEs have been used to successfully target genes in a variety of species, including humans. Depending on the type of functional domain that is fused to the TALE of interest, these proteins can have diverse biological effects. For example, after binding DNA, TALEs fused to transcriptional activation domains can function as robust transcription factors (TALE-TFs), while fused to restriction endonucleases (TALENs) can cut DNA. Targeted genome editing, in theory, is capable of modifying any endogenous gene sequence of interest; this can be performed in cells or organisms, and may be applied to clinical gene-based therapies in the future. With current technologies, highly accurate, specific, and reliable gene editing cannot be achieved. Thus, recognition and binding mechanisms governing TALE biology are currently hot research areas. In this review, we summarize the major advances in TALE technology over the past several years with a focus on the interaction between TALEs and DNA, TALE design and construction, potential applications for this technology, and unique characteristics that make TALEs superior to zinc finger endonucleases.
authors.affiliation: Department of Medical Genetics, College of Basic Medical Science, Third Military Medical University, Chongqing 400038, People's Republic of China; Battalion 16 of Cadet Brigade, Third Military Medical University, Chongqing 400038, People's Republic of China. Electronic address: zhangmingjie1989@hotmail.com.
authors.forename: Mingjie
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Clinical Laboratory, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing 400042, People's Republic of China. Electronic address: Wangfnew@gmail.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: Department of Medical Genetics, College of Basic Medical Science, Third Military Medical University, Chongqing 400038, People's Republic of China.
authors.forename: Shifei
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Medical Genetics, College of Basic Medical Science, Third Military Medical University, Chongqing 400038, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Medical Genetics, College of Basic Medical Science, Third Military Medical University, Chongqing 400038, People's Republic of China. Electronic address: baiyungene@gmail.com.
authors.forename: Yun
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Medical Genetics, College of Basic Medical Science, Third Military Medical University, Chongqing 400038, People's Republic of China. Electronic address: buyi.chu@gmail.com.
authors.forename: Xueqing
authors.initials: X
authors.lastname: Xu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004247:DNA / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D003851:Deoxyribonucleases / Q000737:chemistry / Q000378:metabolism*; D005818:Genetic Engineering / Q000379:methods*; D016678:Genome / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D014157:Transcription Factors; D004247:DNA; D003851:Deoxyribonucleases
keywords: Gene targeting; Genome editing; TALE nucleases; TALE transcription factors; Transcription activator-like effectors