Bacteriophage pRNA is a
ncRNA
A non-coding RNA (ncRNA) is a functional RNA molecule that is not translated into a protein. The DNA sequence from which a functional non-coding RNA is transcribed is often called an RNA gene. Abundant and functionally important types of non ...
element. During replication of linear dsDNA viruses, the viral genome is packaged into the pre-formed viral
procapsid. The packaging of DNA into the procapsid requires a
molecular motor
Molecular motors are natural (biological) or artificial molecular machines that are the essential agents of movement in living organisms. In general terms, a motor is a device that consumes energy in one form and converts it into motion or mech ...
, which uses
ATP as energy to accomplish the energetically unfavorable motion. In some bacteriophage, an RNA (pRNA) molecule is a vital component of this motor.
Structural analyses of the packaging motor have demonstrated that the
pRNA molecule has fivefold symmetry when attached to the prohead.
The pRNA is thought to be bound by the
capsid
A capsid is the protein shell of a virus, enclosing its genetic material. It consists of several oligomeric (repeating) structural subunits made of protein called protomers. The observable 3-dimensional morphological subunits, which may or ma ...
connector protein.
Only the first 120
bases of the pRNA are essential for packing the viral DNA.
The pRNA is proposed to be composed of two domains, one corresponding to the first 120 bases and the second to the remaining 50 bases.
Nuclear cleavage occurs in the single strand region linking these two domains.
References
External links
*
Non-coding RNA
Bacteriophages
{{molecular-cell-biology-stub