Generation and Characterization of Mice Carrying a Conditional Allele of the Wwox Tumor Suppressor Gene

WWOX, the gene that spans the second most common human chromosomal fragile site, FRA16D, is inactivated in multiple human cancers and behaves as a suppressor of tumor growth. Since we are interested in understanding WWOX function in both normal and cancer tissues we generated mice harboring a conditional Wwox allele by flanking Exon 1 of the Wwox gene with LoxP sites. Wwox knockout (KO) mice were developed by breeding with transgenic mice carrying the Cre-recombinase gene under the control of the adenovirus EIIA promoter. We found that Wwox KO mice suffered from severe metabolic defect(s) resulting in growth retardation and all mice died by 3 wk of age. All Wwox KO mice displayed significant hypocapnia suggesting a state of metabolic acidosis. This finding and the known high expression of Wwox in kidney tubules suggest a role for Wwox in acid/base balance. Importantly, Wwox KO mice displayed histopathological and hematological signs of impaired hematopoeisis, leukopenia, and splenic atrophy. Impaired hematopoeisis can also be a contributing factor to metabolic acidosis and death. Hypoglycemia and hypocalcemia was also observed affecting the KO mice. In addition, bone metabolic defects were evident in Wwox KO mice. Bones were smaller and thinner having reduced bone volume as a consequence of a defect in mineralization. No evidence of spontaneous neoplasia was observed in Wwox KO mice. We have generated a new mouse model to inactivate the Wwox tumor suppressor gene conditionally. This will greatly facilitate the functional analysis of Wwox in adult mice and will allow investigating neoplastic transformation in specific target tissues

β-Nitroso-o-Quinone Methides: Potent Intermediates in Organic Chemistry and Biology : The impact of the NO group on their Structure and Reactivity Profile: a Theoretical Insight

The structure and reactivity profile of prototype o-quinone methides 1, 2 and their ß-nitroso analogues 6-9 have been investigated by means of DFT and MP2 calculations. These highly reactive unstable species are generated by oxidative dearomatization of their precursor oximes. The destabilization of their structure is more pronounced in the ß-nitroso congeners 7-9. There is only a weak π conjugation across the nitrosoalkene arm. The latter gives rise to E and Z conformations and causes some distortion on the ring -frame while the π-frame is weakly perturbed. The Z conformation is the most stable in all structures. Their geometry is also affected by the o-quinone ring and the 1,2-(7 and 8) and 2,3-(9) isomer pattern. The stability of these conformations is rationalized in terms of ortho- or peri- ring formations. The impact of their geometry profile on their reactivity pattern has been studied by means of reactivity descriptors such as Fukui function f(r), chemical potential and hardness, HOMO and LUMO energies and their separation (HOMO-LUMO gap) as well as aromaticity indices such as HOMA and out-of-plane deformability. All descriptors consistently demonstrate that the reactivity is dominated by an intramolecular ortho or peri-cyclization mode to fused 1,2-oxazoles or 1,2-oxazines, respectively. Intermolecular primary reactions can occur at the quinone alkene bond or that of the nitrosoalkene arm.Peer reviewe