primary miRNA binding

Definition

Target type: molecularfunction

Binding to a primary microRNA (pri-miRNA) transcript, an RNA molecule that is processed into a short hairpin-shaped structure called a pre-miRNA and finally into a functional miRNA. Both double-stranded and single-stranded regions of a pri-miRNA are required for binding. [GOC:sl, PMID:15531877, PMID:15574589]

Primary miRNA binding, a critical step in microRNA (miRNA) biogenesis, involves the recognition and interaction of specific proteins with the nascent pri-miRNA transcript. This process initiates the formation of the microRNA processing complex, which ultimately leads to the production of mature miRNAs. The molecular function of primary miRNA binding can be broken down into the following key aspects:

1. **Pri-miRNA Recognition:** Specialized proteins, such as Drosha in animals and its plant counterpart, Dicer-like 1 (DCL1), bind to specific structural features within the pri-miRNA molecule. These features include the stem-loop structure formed by base pairing within the pri-miRNA transcript, as well as flanking sequences that provide additional recognition points.
2. **Complex Assembly:** The binding of these proteins to the pri-miRNA triggers the assembly of the microprocessor complex in animals or the DCL1 complex in plants. This complex is crucial for the efficient processing of pri-miRNAs.
3. **Cleavage and Release:** The microprocessor or DCL1 complex processes the pri-miRNA through a precise cleavage event, releasing a hairpin-shaped precursor miRNA (pre-miRNA). This cleavage is typically mediated by the RNase III endonuclease activity of Drosha or DCL1, respectively.
4. **Structural Transformation:** The interaction of the microprocessor or DCL1 complex with the pri-miRNA not only triggers cleavage but also induces a conformational change in the pri-miRNA. This conformational change facilitates the release of the pre-miRNA from the complex.
5. **Specificity and Regulation:** Primary miRNA binding is highly specific, ensuring that only the appropriate pri-miRNAs are selected for processing. This specificity is achieved through the recognition of specific sequence elements within the pri-miRNA and the interaction with specific proteins within the processing complex. The process of primary miRNA binding is tightly regulated, allowing cells to control the levels and types of miRNAs produced, thereby influencing gene expression in response to diverse cellular cues and developmental signals.'
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Proteins (2)

Compounds (38)