Cryptography and miRNAs
You may have never thought of molecular biology as an intriguing cloak and dagger operation complete with coded messages and cryptic communications, but that may change soon. Harry Shaw, staff engineer at National Aeronautics and Space Administration (NASA), is developing a model to attack problems in molecular biology using cryptography tools and communication signals analysis.
“Many types of information are coded, encrypted, and involved in network security. There are similarities between biology and information processing in the real world. For example, in cryptography one looks at ways to provide two services: confidentiality in the form of codes and authentication, which validates the credentials of the sender and ensures that the message is unaltered in transmission.”
According to Shaw, analogous molecular biological processes also seek authentication in recognizing the correct connections via structure and sequence and confidentiality in the form of codes, such as the genetic code, the protein alphabet code of 20 amino acids, and the histone code.
For example, a gene is encrypted when it is not expressed and is decrypted when activated and undergoes transcription, and then subsequently reverts to the encrypted form.
“miRNAs are short sections of noncoding RNAs that induce a broad pattern of protein translation modifications,” Shaw said. Modeling miRNA can be informative. The approach involves building a model employing virtual senders and receivers using miRNA and messenger RNA (mRNA) sequences as message traffic.
A communication channel model can be created to provide a physical context for the message traffic, much like a wireless communications channel. The model allows for coding of secondary structure information on a probabilistic basis using entropy coding (already used in data-compression algorithms). Options for adding spectroscopic information to the encryption process are also being investigated.
The goal of these models is to improve predictions of miRNA and mRNA seed-target binding. The process is extensible to include higher levels of complexity such as inclusion of RNA-induced silencing complex structures.
“Eventually, such models will require validation using functional assays. Once the models are validated and calibrated, the results will foster better ways to engineer miRNAs with more specific binding properties for mRNA. This could help to improve therapies that modulate gene expression,” Shaw added.
The field of miRNA is still young and evolving. Many challenges remain, yet as the methodology continues to advance, new understandings are expected to emerge and spawn potentially impressive therapeutic applications.