22FN: AsCas12a

Cryo-EM structure of AsCas12a in complex with crDNA and RNA target. Determined by electron microscopy at 3.17 Å resolution. Released 29 Apr 2026.

Method

Electron microscopy

Resolution

3.17 Å

Organisms

synthetic construct, Acidaminococcus sp. BV3L6

Chains

3

Atoms

11,105

Mol. weight

178.94 kDa

Released

29 Apr 2026

Explore 22FN in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

22FN contains 61 α-helices and 47 β-strands across 1 chain. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 61 helices, 47 β-strands

Molecules and chains

>22FN_1 RNA (5'-R(P*GP*AP*CP*AP*GP*CP*CP*CP*AP*CP*AP*UP*GP*GP*CP*AP*UP*UP*CP*CP*AP*CP*U)-3') (chains B)
GACAGCCCACAUGGCAUUCCACUUAUCACUGGCAUCCUUCCACUC

>22FN_2 CRISPR-associated endonuclease Cas12a (chains A)
MTQFEGFTNLYQVSKTLRFELIPQGKTLKHIQEQGFIEEDKARNDHYKELKPIIDRIYKT
YADQCLQLVQLDWENLSAAIDSYRKEKTEETRNALIEEQATYRNAIHDYFIGRTDNLTDA
INKRHAEIYKGLFKAELFNGKVLKQLGTVTTTEHENALLRSFDKFTTYFSGFYENRKNVF
SAEDISTAIPHRIVQDNFPKFKENCHIFTRLITAVPSLREHFENVKKAIGIFVSTSIEEV
FSFPFYNQLLTQTQIDLYNQLLGGISREAGTEKIKGLNEVLNLAIQKNDETAHIIASLPH
RFIPLFKQILSDRNTLSFILEEFKSDEEVIQSFCKYKTLLRNENVLETAEALFNELNSID
LTHIFISHKKLETISSALCDHWDTLRNALYERRISELTGKITKSAKEKVQRSLKHEDINL
QEIISAAGKELSEAFKQKTSEILSHAHAALDQPLPTTLKKQEEKEILKSQLDSLLGLYHL
LDWFAVDESNEVDPEFSARLTGIKLEMEPSLSFYNKARNYATKKPYSVEKFKLNFQRPTL
ASGWDVNKEKNNGAILFVKNGLYYLGIMPKQKGRYKALSFEPTEKTSEGFDKMYYDYFPD
AAKMIPKCSTQLKAVTAHFQTHTTPILLSNNFIEPLEITKEIYDLNNPEKEPKKFQTAYA
KKTGDQKGYREALCKWIDFTRDFLSKYTKTTSIDLSSLRPSSQYKDLGEYYAELNPLLYH
ISFQRIAEKEIMDAVETGKLYLFQIYNKDFAKGHHGKPNLHTLYWTGLFSPENLAKTSIK
LNGQAELFYRPKSRMKRMAHRLGEKMLNKKLKDQKTPIPDTLYQELYDYVNHRLSHDLSD
EARALLPNVITKEVSHEIIKDRRFTSDKFLFHVPITLNYQAANSPSKFNQRVNAYLKEHP
ETPIIGIDRGERNLIYITVIDSTGKILEQRSLNTIQQFDYQKKLDNREKERVAARQAWSV
VGTIKDLKQGYLSQVIHEIVDLMIHYQAVVVLENLNFGFKSKRTGIAEKAVYQQFEKMLI
DKLNCLVLKDYPAEKVGGVLNPYQLTDQFTSFAKMGTQSGFLFYVPAPYTSKIDPLTGFV
DPFVWKTIKNHESRKHFLEGFDFLHYDVKTGDFILHFKMNRNLSFQRGLPGFMPAWDIVF
EKNETQFDAKGTPFIAGKRIVPVIENHRFTGRYRDLYPANELIALLEEKGIVFRDGSNIL
PKLLENDDSHAIDTMVALIRSVLQMRNSNAATGEDYINSPVRDLNGVCFDSRFQNPEWPM
DADANGAYHIALKGQLLLNHLKESKDLKLQNGISNQDWLAYIQELRN

>22FN_3 DNA (41-MER) (chains C)
AAGTGGAATGCCATGTGGGCTTAAAGGTGAATCCTTTATTAAT

Primary citation

DNA-guided CRISPR-Cas12a effectors for programmable RNA recognition and cleavage. Wu, X., Lam, W.H., Zhao, Z. et al. Nat Biotechnol (2026). DOI 10.1038/s41587-026-03120-5 · PubMed

Related structures

Other PDB entries of the same protein (UniProt U2UMQ6 (AlphaFold model), which also has an AlphaFold model), best resolution first:

• 5XH6 2.0 Å, Crystal structure of the Acidaminococcus sp. BV3L6 Cpf1 RVR variant in complex with…
• 5XH7 2.0 Å, Crystal structure of the Acidaminococcus sp. BV3L6 Cpf1 RR variant in complex with crRNA…
• 9MK3 2.7 Å, Engineered AsCas12a (M537R, F870L)
• 5B43 2.8 Å, Crystal structure of Acidaminococcus sp. Cpf1 in complex with crRNA and target DNA
• 11VQ 3.18 Å, DNA-guided AsCas12a
• 5KK5 3.29 Å, AsCpf1(E993A)-crRNA-DNA ternary complex
• 8SFL 3.3 Å, WT CRISPR-Cas12a with a 15bp R-loop
• 8SFN 3.3 Å, WT CRISPR-Cas12a with a 16bp R-loop and nontarget strand in the RuvC active site.
• 8SFO 3.3 Å, WT CRISPR-Cas12a with a 20bp R-loop and nontarget strand in the RuvC active site.
• 8SFH 3.4 Å, WT CRISPR-Cas12a with a 5bp R-loop
• 9CJI 3.4 Å, Cas12a:gRNA:DNA (Acidaminococcus sp.) with 0 RNA:DNA base pairs, structure 2
• 8SFI 3.5 Å, WT CRISPR-Cas12a with a 8bp R-loop

Browse structure collections

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