In 2004, the first papers detailing the roles of microRNA in hematopoiesis were published by the labs of David Bartel and Harvey Lodish. Since then, there have been a plethoraof discoveries of how microRNAs influence hematopoiesis, and this has led to a better understanding not only of hematopoeisis but of how microRNAs may function in development in general. Some emerging themes include the idea that some microRNAs act primarily through a single target at critical points of development, or that microRNAs may serve as organizing loci for complex developmental pathways of, finally, that microRNAs connect disparate cellular pathways whose interconnections were previously unrecognized. Our current research has come to focus on microRNAs that are involved in hematopoiesis and the immune response.  One such microRNA, miR-146a, is found to be involved in the regulation of developmental processes in a variety of hematopoietic cells. One angle we are focused on is to understand how NF-kappa B dysregulation may result in the range of myeloid and hematopoeitic phenotypes that we are observing. To do so, we are collaborating with the laboratory of Alex Hoffmann.  Secondly, we are very interested in understanding the role of miR-146a in the immune response.  We have recently published a paper on defective marginal zone B-cell development in miR-146a deficient mice, and collaborated on a manuscript that describes roles for miR-146a in regulating T-cell activation. Studies of how miR-146a regulates B-cell activation and autoimmunity are future focuses of this area of research in the laboratory.