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Oxygen Control Of The Bradyrhizobium Japonicum Hema Gene., Karen M. Page, Mary Lou Guerinot
Oxygen Control Of The Bradyrhizobium Japonicum Hema Gene., Karen M. Page, Mary Lou Guerinot
Dartmouth Scholarship
The hemA gene of Bradyrhizobium japonicum, which encodes the first enzyme in the heme biosynthetic pathway, is regulated by oxygen. Up to ninefold induction of beta-galactosidase activity is seen when cultures of B. japonicum containing either a plasmid-encoded or a chromosomally integrated hemA-lacZ fusion are shifted to restricted aeration. The oxygen effect is mediated via the FixLJ two-component regulatory system, which regulates the expression of a number of genes involved in the nitrogen fixation process in response to low-oxygen conductions; oxygen induction is lost when the hemA-lacZ fusion is expressed in strains of B. japonicum carrying mutations in fixL or …
3 Genes Of The Map Kinase Cascade, Mek-2, Mpk-1/Sur-1 And Let-60 Ras, Are Required For Meiotic Cell-Cycle Progression In Caenorhabditis-Elegans, Diane L. Church, Kun Liang Guan, Eric J. Lambie
3 Genes Of The Map Kinase Cascade, Mek-2, Mpk-1/Sur-1 And Let-60 Ras, Are Required For Meiotic Cell-Cycle Progression In Caenorhabditis-Elegans, Diane L. Church, Kun Liang Guan, Eric J. Lambie
Dartmouth Scholarship
In the germline of Caenorhabditis elegans hermaphrodites, meiotic cell cycle progression occurs in spatially restricted regions. Immediately after leaving the distal mitotic region, germ cells enter meiosis and thereafter remain in the pachytene stage of first meiotic prophase for an extended period. At the dorsoventral gonadal flexure, germ cells exit pachytene and subsequently become arrested in diakinesis. We have found that exit from pachytene is dependent on the function of three members of the MAP kinase signaling cascade. One of these genes, mek-2, is a newly identified C. elegans MEK (MAP kinase kinase). The other two genes, mpk-1/sur-1 (MAP kinase) …
Richard Goldschmidt's "Heresies" And The Evolutionary Synthesis, Michael Dietrich
Richard Goldschmidt's "Heresies" And The Evolutionary Synthesis, Michael Dietrich
Dartmouth Scholarship
No abstract provided.