caa a22 4500 477119271 CHVBK 20180405111631.0 cr unu---uuuuu 170330e19960501xx s 000 0 eng 10.1007/BF00225840 doi (NATIONALLICENCE)springer-10.1007/BF00225840 Profiles of nuclear and mitochondrial encoded mRNAs in developing and quiescent embryos of Artemia franciscana [Elektronische Daten] [Iris Hardewig, Thomas Anchordoguy, Douglas Crawford, Steven Hand] Embryos of the brine shrimp Artemia franciscana are able to withstand long bouts of environmental anoxia by entering a quiescent state during which metabolism is greatly depressed. Recent evidence supports a global arrest of protein synthesis during quiescence. In this study we measured the amounts of mRNA for a mitochondrial-encoded subunit of cytochrome c oxidase (COX I) and for nuclear-encoded actin during aerobic development, anaerobiosis, and aerobic acidosis (artificial quiescence imposed by intracellular acidification under aerobic conditions). The levels of both COX I and actin transcripts increased significantly during aerobic development. COX I mRNA levels were tightly correlated with previous measures of COX catalytic activity, which suggests that COX synthesis could be regulated by message concentration during aerobic development. The ontogenetic increase for these mRNAs was blocked by anoxia and aerobic acidosis. Importantly, the levels of COX I and actin mRNA did not decline appreciably during the 6 h bouts of quiescence, even though protein synthesis is acutely arrested by these same treatments. Thus, the constancy of mRNA levels during quiescence indicate that reduced protein synthesis is not caused by message limitation, but rather, is likely controlled at the translational level. One advantage of this regulatory mechanism is the conservation of mRNA molecules during quiescence, which would potentially favor a quick resumption of translation as soon as oxygen is returned to the embryos. Finally, because anoxia and aerobic acidosis are both characterized by acidic intracellular pH, the reduction in pH may serve, directly or indirectly, as one signal regulating levels of mRNA in this embryo during quiescence. Kluwer Academic Publishers, 1996 actin nationallicence anoxia nationallicence Artemia nationallicence cytochrome c oxidase nationallicence messenger RNA nationallicence transcription nationallicence Hardewig Iris Department of EPO Biology, University of Colorado, 80309-0334, Boulder, CO aut Anchordoguy Thomas Department of EPO Biology, University of Colorado, 80309-0334, Boulder, CO aut Crawford Douglas Department of Organismal Biology and Anatomy, University of Chicago, 60637, Chicago, IL, USA aut Hand Steven Department of EPO Biology, University of Colorado, 80309-0334, Boulder, CO aut Molecular and Cellular Biochemistry Kluwer Academic Publishers 158/2(1996-05-01), 139-147 0300-8177 158:2<139 1996 158 11010 https://doi.org/10.1007/BF00225840 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00225840 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Hardewig Iris Department of EPO Biology, University of Colorado, 80309-0334, Boulder, CO aut NATIONALLICENCE 700 1- Anchordoguy Thomas Department of EPO Biology, University of Colorado, 80309-0334, Boulder, CO aut NATIONALLICENCE 700 1- Crawford Douglas Department of Organismal Biology and Anatomy, University of Chicago, 60637, Chicago, IL, USA aut NATIONALLICENCE 700 1- Hand Steven Department of EPO Biology, University of Colorado, 80309-0334, Boulder, CO aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Kluwer Academic Publishers 158/2(1996-05-01), 139-147 0300-8177 158:2<139 1996 158 11010 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer