scholarly journals Complex patterns of sequence variation and multiple 5‘ and 3‘ ends are found among transcripts of the erythroid ankyrin gene

1993 ◽  
Vol 268 (13) ◽  
pp. 9533-9540
Author(s):  
C.S. Birkenmeier ◽  
R.A. White ◽  
L.L. Peters ◽  
E.J. Hall ◽  
S.E. Lux ◽  
...  
Author(s):  
Eric Gubel

Rooted in Late Bronze Age Levantine traditions, Phoenician art emerges in the early first millennium bce, spiced with new elements adopted and adapted from contemporary Egyptian models, while also permeable to influence from artistic trends popular with neighboring cultures and overseas recipients of Phoenician luxurious exports. During its acme between the late ninth and early seventh centuries bce, the art shared a common repertoire of motifs among sculptors, metalsmiths, ivory carvers, and seal cutters in a predominantly Egyptianizing style. Mass-produced terracotta plaques, figurines, and the minor arts displayed a more diversified array of autochthonous characteristics. In line with the evolution of sculpture, the Cypriot component was definitely replaced by Greek idioms from the later sixth century bce onward. If Punic art cannot possibly be defined as a mere perpetuation of the Phoenician production, and was impacted by more complex patterns of cultural interaction (e.g. North Africa, Iberia), the latter’s heritage is undeniable in many artistic media.


PLoS ONE ◽  
2012 ◽  
Vol 7 (9) ◽  
pp. e46150 ◽  
Author(s):  
Clea Scala ◽  
Xiangjun Tian ◽  
Natasha J. Mehdiabadi ◽  
Margaret H. Smith ◽  
Gerda Saxer ◽  
...  

Genetics ◽  
2002 ◽  
Vol 161 (4) ◽  
pp. 1609-1623 ◽  
Author(s):  
Christopher Toomajian ◽  
Martin Kreitman

AbstractThe HFE locus encodes an HLA class-I-type protein important in iron regulation and segregates replacement mutations that give rise to the most common form of genetic hemochromatosis. The high frequency of one disease-associated mutation, C282Y, and the nature of this disease have led some to suggest a selective advantage for this mutation. To investigate the context in which this mutation arose and gain a better understanding of HFE genetic variation, we surveyed nucleotide variability in 11.2 kb encompassing the HFE locus and experimentally determined haplotypes. We fully resequenced 60 chromosomes of African, Asian, or European ancestry as well as one chimpanzee, revealing 41 variable sites and a nucleotide diversity of 0.08%. This indicates that linkage to the HLA region has not substantially increased the level of HFE variation. Although several haplotypes are shared between populations, one haplotype predominates in Asia but is nearly absent elsewhere, causing higher than average genetic differentiation among the three major populations. Our samples show evidence of intragenic recombination, so the scarcity of recombination events within the C282Y allele class is consistent with selection increasing the frequency of a young allele. Otherwise, the pattern of variability in this region does not clearly indicate the action of positive selection at this or linked loci.


Ecotoxicology ◽  
2021 ◽  
Author(s):  
Daesik Park ◽  
Catherine R. Propper ◽  
Guangning Wang ◽  
Matthew C. Salanga

AbstractNaturally occurring arsenic is toxic at extremely low concentrations, yet some species persist even in high arsenic environments. We wanted to test if these species show evidence of evolution associated with arsenic exposure. To do this, we compared allelic variation across 872 coding nucleotides of arsenic (+3) methyltransferase (as3mt) and whole fish as3mt gene expression from three field populations of Gambusia affinis, from water sources containing low (1.9 ppb), medium-low (3.3 ppb), and high (15.7 ppb) levels of arsenic. The high arsenic site exceeds the US EPA’s Maximum Contamination Level for drinking water. Medium-low and high populations exhibited homozygosity, and no sequence variation across all animals sampled. Eleven of 24 fish examined (45.8%) in the low arsenic population harbored synonymous single nucleotide polymorphisms (SNPs) in exons 4 and/or 10. SNP presence in the low arsenic population was not associated with differences in as3mt transcript levels compared to fish from the medium-low site, where SNPs were noted; however, as3mt expression in fish from the high arsenic concentration site was significantly lower than the other two sites. Low sequence variation in fish populations from sites with medium-low and high arsenic concentrations suggests greater selective pressure on this allele, while higher variation in the low population suggests a relaxed selection. Our results suggest gene regulation associated with arsenic detoxification may play a more crucial role in influencing responses to arsenic than polymorphic gene sequence. Understanding microevolutionary processes to various contaminants require the evaluation of multiple populations across a wide range of pollution exposures.


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