Mouse Model to Study the miR-15a/16-1 MicroRNA Cluster in Chronic Lymphocytic Leukemia and Cell Cycle Progression

Mouse Model to Study the miR-15a/16-1 MicroRNA Cluster in Chronic Lymphocytic Leukemia and Cell Cycle Progression

Problem or Unmet Need

Chronic lymphocytic leukemia (CLL) pathogenesis has been associated with many genetic aberrations. The most common is the deletion of chromosomal region 13q14, which encodes the DLEU2 gene (deleted in leukemia 2), and the miR15-a/16-1 microRNA cluster. A conditional knockout of this entire region was generated simultaneously and was shown to recapitulate the full spectrum of human CLL disease pathogenesis (IR 2807-MDR TechBrief). However, it was unclear whether DLEU2, a gene with unknown function, or the miR15-a/16-1 cluster was mediating the phenotypes. Furthermore, work from other researchers using in vitro cell culture systems have implicated this cluster as a negative regulator of cell proliferation and programmed cell death. However, the in vivo role of this microRNA cluster in cell cycle progression and CLL pathogenesis requires further characterization.

Details of the Invention

A conditional knockout mouse was generated that specifically deletes the miR15-a/16-1 cluster. The microRNA cluster is flanked with sites for a recombinase, which allows for in vivo deletion of the intervening micoRNA cluster, while maintaining the integrity of the surrounding genes, in particular DLEU2. This allows the investigator to tease the functional contribution of both the microRNA cluster and DLEU2 in CLL pathogenesis. Furthermore, it provides a mouse model to study the role of miR15-a/15-1 in cell cycle control in other cell types.

Applications:

• Mouse model to assess the contribution of the miR15-a/16-1 cluster in CLL pathogenesis
• Mouse model to test computer predicted miR15-a/16-1 target genes
• Mouse model to study the role of miR15-a/16-1 cluster in cell cycle progression

Advantages:

• Conditional deletion allows the researcher to breed with mouse lines that have the recombinase under pharmacological and/or cell-type or tissue specific promoters for temporal and spatial deletion of the microRNA cluster to determine when and where this cluster is of importance.
• Can be crossed with mouse lines containing reporter constructs of predicted miR15-a/16-1 target genes to demonstrate in vivo regulation by miR-15a/16-1.
• Strain can also be crossed to mouse lines containing knockouts of miR15-a/16-1 target genes to determine the contribution of each target gene to the miR15-a/16-1 knockout phenotype.
• Unlike in vitro cell culture systems, the mouse model allows investigators to study the microRNA’s functional role under physiological settings.

Lead Inventor:

Riccardo Dalla-Favera, M.D.

Patent Information:

Patent Pending

Related Publications:

• Klein U, Lia M, Crespo M, Siegel R, Shen Q, Mo T, Ambesi-Impiombato A, Califano A, Migliazza A, Bhagat G, Dalla-Favera R. “The DLEU2/miR-15a/16-1 cluster controls B cell proliferation and its deletion leads to chronic lymphocytic leukemia” Cancer Cell. 2010 Jan 19; 17(1): 28-40.

Tech Ventures Reference:

• IR 2807

• Licensing Contact: Joan Martinez