Browsing by Subject "Copepods"

Now showing 1 - 2 of 2

Host-parasite interactions at the genetic level in the Schistocephalus solidus tapeworm, copepods, and threespine stickleback system
(2022-05-06) Shim, Kum C.; Juenger, Thomas; Bolnick, Daniel; Kirkpatrick, Mark; Matz, Mikhail; Nice, Chris
In chapter one I surveyed the genetic structuring of 12 Schistocephalus solidus tapeworm populations from Vancouver Island, BC, and compared it to that of their threespine stickleback fish hosts. There were small but significant genetic differences among the tapeworm populations, and these genetic differences were significantly smaller than those of the fish. The latter indicates that the parasite disperses more readily than their fish hosts. In Chapter two, I investigated if there was local adaptation and host specify of the tapeworm to its copepod hosts. Results indicate that the tapeworm is not locally adapted to the copepods, but there was host specificity as a copepod genus was more parasitized than another genus. In chapter three, I explored if stickleback host immunity can cause divergent selection in the tapeworm. Indeed, there were at least eight loci under divergent selection in tapeworm populations caused by a strong immunological respond to infection from the fish.
Very Bright Green Fluorescent Proteins from the Pontellid Copepod Pontella mimocerami
(Public Library of Science, 2010-07-14) Hunt, Marguerite E.; Scherrer, Michael P.; Ferrari, Frank D.; Matz, Mikhail V.
Background -- Fluorescent proteins (FP) homologous to the green fluorescent protein (GFP) from the jellyfish Aequorea victoria have revolutionized biomedical research due to their usefulness as genetically encoded fluorescent labels. Fluorescent proteins from copepods are particularly promising due to their high brightness and rapid fluorescence development. Results -- Here we report two novel FPs from Pontella mimocerami (Copepoda, Calanoida, Pontellidae), which were identified via fluorescence screening of a bacterial cDNA expression library prepared from the whole-body total RNA of the animal. The proteins are very similar in sequence and spectroscopic properties. They possess high molar extinction coefficients (79,000 M−1 cm−) and quantum yields (0.92), which make them more than two-fold brighter than the most common FP marker, EGFP. Both proteins form oligomers, which we were able to counteract to some extent by mutagenesis of the N-terminal region; however, this particular modification resulted in substantial drop in brightness. Conclusions -- The spectroscopic characteristics of the two P. mimocerami proteins place them among the brightest green FPs ever described. These proteins may therefore become valuable additions to the in vivo imaging toolkit.