TALENs, or Transcription Activator-Like Effector Nucleases, are a type of engineered protein used in genetic engineering. They consist of a DNA-binding domain that can be designed to target specific sequences of DNA and a nuclease domain that cuts the DNA at that location. This allows scientists to make precise edits to the genome of various organisms. TALENs are valuable tools in fields like biotechnology and medicine, as they can be used for gene therapy, creating genetically modified organisms, and studying gene function. Their ability to target specific genes makes them a powerful alternative to other gene-editing technologies like CRISPR.