The invention discloses a construction method of an HDAC5
gene knockout BHK-21
cell line, which comprises the following steps: carrying out
gene knockout on HDAC5 in a
cell line BHK-21 for foot-and-mouth
disease vaccine production by utilizing a
CRISPR / Cas9 technology, transfecting BHK-21 cells by utilizing
CRISPR plasmids for knocking out the HDAC5, and separating the cells to obtain a plurality of
cell clones by utilizing antibiotic screening in combination with gradient
dilution and a
cloning ring method; extracting the
genome DNA, performing PCR amplification and sequencing and successfully identifying the cell
cloning of which one HDAC5
gene is subjected to homozygous
frameshift mutation, wherein the HDAC5-KO-A2 has deletion of 13 basic groups at a Cas9 predetermined
cutting position. In the HDAC5 knockout BHK-21 cell line, the replication rate of foot-and-mouth
disease virus is obviously accelerated, the final
virus titer is obviously improved, and the HDAC5 knockout has no obvious influence on the
cell growth rate, so that the HDAC5 knockout BHK-21 cell line has the prospect of being used for foot-and-mouth
disease vaccine production. Therefore, the foundation is laid for further knocking out HDAC5 from
suspension culture type BHK-21 cells and directly applying HDAC5 to production of foot-and-mouth disease vaccines.