Lycophyte plastid genomics: extreme variation inGC, gene and intron content and multiple inversions between a direct and inverted orientation of therRNArepeat

The promoter of the human thymidine kinase gene was defined by DNA sequence and genetic analyses. Mutant plasmids with deletions extending into the promoter region from both the 5' and 3' directions were constructed. The mutants were tested in a gene transfer system for the ability to transform TK- cells to the TK+ phenotype. This analysis delimited the functional promoter to within an 83-base-pair region upstream of the mRNA cap site. This region contains sequences common to other eucaryotic promoters including G X C-rich hexanucleotides, a CAAT box, and an A X T-rich region. The CAAT box is in an inverted orientation and is part of a 9-base-pair sequence repeated twice in the promoter region. Comparison of the genomic sequence with the cDNA sequence defined the first exon of the thymidine kinase gene.

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The new Belostoma fittkaui species group with supplemental descriptions of B. fittkaui De Carlo and B. sayagoi De Carlo

Zootaxa ◽

10.11646/zootaxa.4942.4.6 ◽

2021 ◽

Vol 4942 (4) ◽

pp. 583-591

Author(s):

FABIANO STEFANELLO

Keyword(s):

New Species ◽

South America ◽

Comparative Morphology ◽

Species Group ◽

Type Material ◽

Extreme Variation ◽

Species Groups ◽

A New Species ◽

Tropical South America

The giant water bug fauna from tropical South America remains poorly known. Three species of Belostoma Latreille (Belostoma fittkaui De Carlo, B. sayagoi De Carlo and B. hirsutum Roback & Nieser) have been cited only a few times in the literature. These three species are remarkable since they represent an extreme variation for the genus, with article II of the labium distinctly shorter than article III. Here, the synonymy of B. hirsutum with B. sayagoi is proposed based on examination of type material and additional specimens. Further, B. fittkaui and B. sayagoi are redescribed, including discussion about comparative morphology with congeners. A new species group is proposed for these species and a key to the Belostoma species groups is provided. Distribution records are also updated.

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Genetic analysis of the human thymidine kinase gene promoter

Molecular and Cellular Biology ◽

10.1128/mcb.6.8.2903-2909.1986 ◽

1986 ◽

Vol 6 (8) ◽

pp. 2903-2909

Author(s):

J A Kreidberg ◽

T J Kelly

Keyword(s):

Thymidine Kinase ◽

Base Pair ◽

Promoter Region ◽

Genomic Sequence ◽

Gene Promoter ◽

Thymidine Kinase Gene ◽

Rich Region ◽

Kinase Gene ◽

Inverted Orientation ◽

Pair Sequence

The promoter of the human thymidine kinase gene was defined by DNA sequence and genetic analyses. Mutant plasmids with deletions extending into the promoter region from both the 5' and 3' directions were constructed. The mutants were tested in a gene transfer system for the ability to transform TK- cells to the TK+ phenotype. This analysis delimited the functional promoter to within an 83-base-pair region upstream of the mRNA cap site. This region contains sequences common to other eucaryotic promoters including G X C-rich hexanucleotides, a CAAT box, and an A X T-rich region. The CAAT box is in an inverted orientation and is part of a 9-base-pair sequence repeated twice in the promoter region. Comparison of the genomic sequence with the cDNA sequence defined the first exon of the thymidine kinase gene.

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Extreme Variation of mtDNA Neutral Substitution Rate across Mammalian Species - the Longevity Hypothesis

Molecular Biology and Evolution ◽

10.1093/molbev/msn033 ◽

2008 ◽

Vol 25 (4) ◽

pp. 795-795 ◽

Cited By ~ 2

Author(s):

B Nabholz ◽

S Glemin ◽

N Galtier

Keyword(s):

Substitution Rate ◽

Mammalian Species ◽

Extreme Variation

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Extreme variation of sulfur isotopic compositions in pyrite from the Qiuling sediment-hosted gold deposit, West Qinling orogen, central China: an in situ SIMS study with implications for the source of sulfur

Mineralium Deposita ◽

10.1007/s00126-015-0597-9 ◽

2015 ◽

Vol 50 (6) ◽

pp. 643-656 ◽

Cited By ~ 38

Author(s):

Lei Chen ◽

Xian-hua Li ◽

Jian-wei Li ◽

Albert H. Hofstra ◽

Yu Liu ◽

...

Keyword(s):

Gold Deposit ◽

Central China ◽

Qinling Orogen ◽

West Qinling ◽

Isotopic Compositions ◽

Extreme Variation ◽

West Qinling Orogen

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Directional learning, but no spatial mapping by rats performing a navigational task in an inverted orientation

Neurobiology of Learning and Memory ◽

10.1016/j.nlm.2010.01.007 ◽

2010 ◽

Vol 93 (4) ◽

pp. 495-505 ◽

Cited By ~ 18

Author(s):

Stephane Valerio ◽

Benjamin J. Clark ◽

Jeremy H.M. Chan ◽

Carlton P. Frost ◽

Mark J. Harris ◽

...

Keyword(s):

Spatial Mapping ◽

Inverted Orientation ◽

Directional Learning

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Wolffish antifreeze protein genes are primarily organized as tandem repeats that each contain two genes in inverted orientation

Molecular and Cellular Biology ◽

10.1128/mcb.8.9.3670-3675.1988 ◽

1988 ◽

Vol 8 (9) ◽

pp. 3670-3675

Author(s):

G K Scott ◽

P H Hayes ◽

G L Fletcher ◽

P L Davies

Keyword(s):

Tandem Repeats ◽

Sea Water ◽

Transcription Termination ◽

Antifreeze Protein ◽

The Other ◽

Direct Repeats ◽

Inverted Orientation ◽

Single Region ◽

Flanking Sequences ◽

Anarhichas Lupus

The antifreeze protein genes of the wolffish (Anarhichas lupus) constitute a large multigene family of 80 to 85 copies, which can be classified into two sets. One-third of the genes were linked but irregularly spaced. The other two-thirds were organized as 8-kilobase-pair (kbp) tandem direct repeats that each contained two genes in inverted orientation; DNA sequence analysis suggests that both genes are functional. Except for a single region specific to each gene, the genes and their immediate flanking sequences were 99.2% identical. This degree of identity ended soon after a putative transcription termination sequence; as the 3' ends of the genes were only 1.3 kbp apart, these sequences might confer mutual protection from interference by transcriptional runoff. A Southern blot of wolffish DNA restricted with enzymes that do not cut within the tandem repeats indicated that the repeats were clustered in groups of six or more. The organization of antifreeze protein genes in the wolffish was very similar to that in the unrelated winter flounder, which produces a completely different antifreeze. This similarity might reflect common dynamics by which their progenitors adapted to life in ice-laden sea water.

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