Rapid Screening of Gene Function by Systemic Delivery of Morpholino Oligonucleotides to Live Mouse Embryos

Traditional gene targeting methods in mice are complex and time consuming, especially when conditional deletion methods are required. Here, we describe a novel technique for assessing gene function by injection of modified antisense morpholino oligonucleotides (MOs) into the heart of mid-gestation mouse embryos. After allowing MOs to circulate through the embryonic vasculature, target tissues were explanted, cultured and analysed for expression of key markers. We established proof-of-principle by partially phenocopying known gene knockout phenotypes in the fetal gonads (Stra8, Sox9) and pancreas (Sox9). We also generated a novel double knockdown of Gli1 and Gli2, revealing defects in Leydig cell differentiation in the fetal testis. Finally, we gained insight into the roles of Adamts19 and Ctrb1, genes of unknown function in sex determination and gonadal development. These studies reveal the utility of this method as a means of first-pass analysis of gene function during organogenesis before committing to detailed genetic analysis.     

Morphological indices and otolith microstructure of Atlantic croaker,Micropogonias undulatus,as indicators of habitat quality along an estuarine pollution gradient

Synopsis Atlantic croaker, Micropogonias undulatus, sampled from a transect along a pollution gradient show a trend of declining growth and physical condition. This trend is apparent in the mean size of 0-group croaker, in their recent growth rate measured by marginal otolith increment widths, in longer term growth rate as indicated by relative otolith weights, and in general physical condition as measured by an index of condition of the caudal fin. We suggest that these measures are indicators of stress associated with environmental conditions. Because croaker from different positions along the pollution gradient were distinguishable, it appears that they remain for extended periods within areas of degraded environmental quality.     

Invited review: Identifying new mouse models of cardiovascular disease: a review of high-throughput screens of mutagenized and inbred strains.

The mouse is a proven model for studying human disease. Many strains exist that exhibit either natural or engineered genetic variation and thereby enable the elucidation of pathways involved in the development of cardiovascular disease. Although those mouse models have been fundamental to advancing our knowledge base, we are still at an early stage in understanding how genes contribute to complex disorders. There remains a need for new animal models that closely represent human disease. To expedite their development, we have established the Center for New Mouse Models of Heart, Lung, Blood, and Sleep Disorders at The Jackson Laboratory. We are using a phenotype-driven approach to identify mutations leading to atherosclerosis, hypertension, obesity, blood disorders, lung dysfunction, thrombosis, and disordered sleep. Our high-throughput, comprehensive phenotyping draws from two sources for new models: 1) the natural variation among over 40 inbred mouse strains and 2) chemically induced, whole-genome mutagenized mice. Here, we review our cardiovascular screens and present some hypertensive, obese, and cardiovascular models identified with this approach.