An increasing body of evidence suggests that mechanisms related to the introduction and repair of DNA double strand breaks (DSBs) may be associated with long-term memory (LTM) processes. Previous studies from our group suggested that factors known to function in DNA recombination/repair machineries, such as DNA ligases, polymerases, and DNA endonucleases, play a role in LTM. Here we report data...

Recent studies have demonstrated that DNA cleavage during V(D)J recombination is mediated by the RAG1 and RAG2 proteins. These proteins must therefore bind to the recombination signals, but the specific binding interaction has been difficult to study in vitro. Here, we use an in vivo one-hybrid DNA binding assay to demonstrate that RAG1, in the absence of RAG2, can mediate signal recognition vi...

Hematopoietic stem and progenitor cells (HSPCs) can produce all kind of blood lineage cells, and gut microbiota that consists of various species of microbe affects development and maturation of the host immune system including gut lymphoid cells and tissues. However, the effect of altered gut microbiota composition on homeostasis of HSPCs remains unclear. Here we show that compositional change ...

Mattson DL, Lund H, Guo C, Rudemiller N, Geurts AM, Jacob H. Genetic mutation of recombination activating gene 1 in Dahl salt-sensitive rats attenuates hypertension and renal damage. Am J Physiol Regul Integr Comp Physiol 304: R407–R414, 2013. First published January 30, 2013; doi:10.1152/ajpregu.00304.2012.—Hypertension and renal damage in Dahl SS rats are associated with increased infiltratin...

IL-17A and IL-17F regulate granulopoiesis and are produced by memory T cells. Rag1(-/-) recombinase-activating gene-deficient mice cannot produce mature T cells but maintain normal neutrophil counts. Athymic nude mice are neutropenic or have near-normal neutrophil counts, depending on the prevailing intestinal flora, and do not produce IL-17A. By contrast, thymi from Rag1(-/-) mice contain as m...

RAG1/GFP knock-in mice were used to precisely chart the emergence and expansion of cells that give rise to the immune system. Lymphopoietic cells detectable in stromal co-cultures arose as early as E8.5, i.e. prior to establishment of the circulation within the paraaortic splanchnopleura (P-Sp). These cells were Tie2+ RAG1- CD34(Lo/-) Kit+ CD41-. While yolk sac (YS) also contained lymphopoietic...

We isolated a mutant, rag17, which is impaired in glucose induction of expression of the major glucose transporter gene RAG1. The RAG17 gene encodes a protein 87% identical to S. cerevisiae enolases (Eno1 and Eno2). The Kleno null mutant showed no detectable enolase enzymatic activity and has severe growth defects on glucose and gluconeogenic carbon sources, indicating that K. lactis has a sing...

Probiotics are viable microorganisms that are increasingly used for treatment of a variety of diseases. Occasionally, however, probiotics may have adverse clinical effects, including septicemia. Here we examined the role of the intestinal microbiota and the adaptive immune system in preventing translocation of probiotics (e.g., Escherichia coli Nissle). We challenged C57BL/6J mice raised under ...