7 research outputs found
The Vehicle, Fall 1987
Table of Contents
Sketches in the SunRodger L. Patiencepage 3
Reflecting PoolRob Montgomerypage 5
Grandpa\u27s Porcelain DollRichard E. Hallpage 6
Tintype 1837Catherine Friemannpage 6
PhotographSteven M. Beamerpage 7
Washerwoman\u27s SongBob Zordanipage 8
Scrambled Eggs for D.O.Lynne A. Rafoolpage 8
my mother would sayMonica Grothpage 9
Retired by His ChildrenDan Von Holtenpage 10
I am the oldestMonica Grothpage 11
Ice on WheatRob Montgomerypage 12
The Nature of the RoseTroy Mayfieldpage 12
Past NebraskaDan Hornbostelpage 13
Five Minute Jamaican VacationChristy Dunphypage 14
PhotographSteven M. Beamerpage 14
The Angry PoemChristy Dunphypage 15
Road UnfamiliarChristy Dunphypage 15
raised voicesMonica Grothpage 16
Old Ladies & MiniskirtsKara Shannonpage 17
FreakspeakBob Zordanipage 18
PortraitDan Von Holtenpage 18
Mobile VacuumKathleen L. Fairfieldpage 19
Rev. Fermus DickSteve Hagemannpage 20
PhotographSteven M. Beamerpage 21
What\u27s the Name of That Flower?Richard Jesse Davispage 22
RequestChristy Dunphypage 23
SketchPaul Seabaughpage 24
ExperiencedMarilyn Wilsonpage 26
Leaving: Two ViewsTina Phillipspage 27
AntaeusDan Von Holtenpage 28
Misogyny at 19J. D. Finfrockpage 29
A Mental CrippleSteve Hagemannpage 32
AssociationsRhonda Ealypage 33
Banana BreadGail Bowerpage 34
Bill and JackBradford B. Autenpage 35
After Image No. 2Rob Montgomerypage 35
VrrooomBeth Goodmanpage 36
Mr. Modern LoverMolly Maddenpage 36
TravelogueRodger L. Patiencepage 37
Down the HighwayJoan Sebastianpage 38
A Retread HeavenRob Montgomerypage 41
StuporDan Von Holtenpage 42
Love Poem After a Seizure in Your BedBob Zordanipage 43
PalsyChristy Dunphypage 44
Interview with Mr. MatthewsBob Zordanipage 45
Chasing Down Hot Air Balloons on a Sunday MorningRob Montgomerypage 48https://thekeep.eiu.edu/vehicle/1049/thumbnail.jp
Physical Analyses of E. coli Heteroduplex Recombination Products In Vivo: On the Prevalence of 5′ and 3′ Patches
BACKGROUND: Homologous recombination in Escherichia coli creates patches (non-crossovers) or splices (half crossovers), each of which may have associated heteroduplex DNA. Heteroduplex patches have recombinant DNA in one strand of the duplex, with parental flanking markers. Which DNA strand is exchanged in heteroduplex patches reflects the molecular mechanism of recombination. Several models for the mechanism of E. coli RecBCD-mediated recombinational double-strand-end (DSE) repair specify that only the 3'-ending strand invades the homologous DNA, forming heteroduplex in that strand. There is, however, in vivo evidence that patches are found in both strands. METHODOLOGY/PRINCIPLE FINDINGS: This paper re-examines heteroduplex-patch-strand polarity using phage lambda and the lambdadv plasmid as DNA substrates recombined via the E. coli RecBCD system in vivo. These DNAs are mutant for lambda recombination functions, including orf and rap, which were functional in previous studies. Heteroduplexes are isolated, separated on polyacrylamide gels, and quantified using Southern blots for heteroduplex analysis. This method reveals that heteroduplexes are still found in either 5' or 3' DNA strands in approximately equal amounts, even in the absence of orf and rap. Also observed is an independence of the RuvC Holliday-junction endonuclease on patch formation, and a slight but statistically significant alteration of patch polarity by recD mutation. CONCLUSIONS/SIGNIFICANCE: These results indicate that orf and rap did not contribute to the presence of patches, and imply that patches occurring in both DNA strands reflects the molecular mechanism of recombination in E. coli. Most importantly, the lack of a requirement for RuvC implies that endonucleolytic resolution of Holliday junctions is not necessary for heteroduplex-patch formation, contrary to predictions of all of the major previous models. This implies that patches are not an alternative resolution of the same intermediate that produces splices, and do not bear on models for splice formation. We consider two mechanisms that use DNA replication instead of endonucleolytic resolution for formation of heteroduplex patches in either DNA strand: synthesis-dependent-strand annealing and a strand-assimilation mechanism