Invertebrates proteins

Several large invertebrate protein complexes have considerable historical significance and are particularly useful as controls for specimen preparation, STEM imaging, and image analysis. These include a wide variety of giant hemoglobins... 

Cyprid major protein is a larval storage protein necessary for successful metamorphosis. " Production of cyprid major protein was increased in the barnacle Balanus amphitrite following exposure to both nonylphenol and estradiol, suggesting that it may be a potential biomarker of estrogen exposure in invertebrates such as barnacles. " "... 

It is obvious from the provisional risk assessment values for microcystins, and, being of the same order of magnitude of mammalian toxicity, similar values may be calculated for the cyanobacterial neurotoxins, that sensitive detection methods are required to detect these low concentrations of toxins. Of the biological methods of detection discussed earlier, the mouse and invertebrate bioassays are not sensitive enough without concentration of water samples, in that they are only able to detect mg of microcystins per litre. Only the immunoassays (ng-/rg 1 and the protein phosphatase inhibition assays (ng O... 

FIGURE 6.7 The three-dimensional structures of two proteins that contain substantial amounts of rx-helix in their structures. The helices are represented by the regularly coiled sections of the ribbon drawings. Myohemery-thrin is the oxygen-carrying protein in certain invertebrates, including Sipunculids, a phylum of marine worm. (Jane Richardson)... 

The oxygen-carrying function is performed in some invertebrates by haemerythrin which, in spite of its name, does not contain haem. It is a diiron-oxygen protein. See K. K. Anderson and A. Gralund, Adv. Inorg. Chem. 43, 359-408 (1995). 

Water birds have not been shown to be directly affected by acidification. However, the prey of waterbirds may be of concern as these lower food-chain organisms may have elevated levels of toxic metals related to acidification of their habitat. Moreover, most water birds rely on some component of the aquatic food-chain for their high protein diet. Invertebrates that normally supply caJcium to egg-laying birds or their growing chicks are among the first to disappear as lakes acidify. As these food sources are reduced or eliminated due to acidification, bird habitat is reduced and reproductive rate of the birds is affected. The Common Loon is able to raise fewer chicks, or none at all, on acidic lakes where fish populations are reduced 37 and 5S). However, in some isolated cases, food supplies can be increased when competitive species are eliminated (e.g.. Common Goldeneye ducks can better exploit insects as food when competition from fish is eliminated). The collective influences of acidification are difficult to quantify on a specific area basis but for species that rely on a healthy aquatic ecosystem to breed, acidification remains a continuing threat in thousands of lakes across eastern North America 14). 

Carotenoids are essential to plants for photosynthesis, acting in light harvesting and especially in protection against destructive photooxidation. Without carotenoids, photosynthesis in an oxygenic atmosphere would be impossible. Some animals use carotenoids for coloration, especially birds (yellow and red feathers), fish and a wide variety of invertebrate animals, where complexation with protein may modify then-colors to blue, green or purple. ... 

Specific carotenoid-protein complexes have been reported in plants and invertebrates (cyanobacteria, crustaceans, silkworms, etc.), while data on the existence of carotenoproteins in vertebrates are more limited. As alternatives for their water solubilization, carotenoids could use small cytosolic carrier vesicles." Carotenoids can also be present in very fine physical dispersions (or crystalline aggregates) in aqueous media of oranges, tomatoes, and carrots. Thus these physicochemical characteristics of carotenoids as well as those of other pigments are important issues for the understanding of their bioavailability. 

Biogenic amines are decarboxylated derivatives of tyrosine and tryptophan that are found in animals from simple invertebrates to mammals. These compounds are found in neural tissue, where they function as neurotransmitters, and in non-neural tissues, where they have a variety of functions. The enzymes involved in biogenic amine synthesis and many receptors for these compounds have been isolated from both invertebrate and vertebrate sources. In all cases, the individual proteins that effect biogenic amine metabolism and function show striking similarity between species, indicating that these are ancient and well-conserved pathways. 

Bhosale, P. and P. S. Bernstein (2007). Vertebrate and invertebrate carotenoid-binding proteins. Arch. Biochem. Biophys. 458(2) 121-127. 

HA receptors are classified into 4 subtypes Hi, H2, H3, and H4 (Hill et al, 1997). All four HA receptor types are metabotropic receptors and belong to the superfamily of G-protein coupled receptors. Ionotropic HA receptors are found in invertebrates (Hardie, 1989 Gisselmann et al., 2002) but are absent from vertebrates (Haas Panula, 2003). Of the four HA receptors, only the Hi, H2, and H3 receptors are found in brain. The recently discovered H4 receptor is predominantly present on leukocytes and may have a critical role in the immune system (Nguyen et al., 2001 Bakker, 2004 Haas 8i Panula, 2003). 

The other major class of extracellular LBPs of mammals is the lipocalins (Flower, 1996). These are approximately 20 kDa, P-sheet-rich proteins, performing functions such as the transport of retinol in plasma or milk, the capture of odorants in olfaction, invertebrate coloration, dispersal of pheromones, and solubilizing the lipids in tears (Flower, 1996). The retinol-binding protein (RBP) of human plasma is found in association with a larger protein, transthyretin, the complex being larger than the kidney threshold and thus not excreted, although the RBP itself may dissociate from the complex to interact with cell surface receptors in the delivery of retinol (Papiz et al., 1986 Sundaram et al., 1998). 

Secondary structural predictions about NPAs, and direct biophysical measurements, have demonstrated that the NPAs are rich in a-helix, with no p-structure either predicted from secondary structure prediction algorithms, or detected by circular dichroism (Kennedy et al, 1995b). In this they are the antithesis of the similarly sized cLBPs and lipocalins. The predictions are that each individual NPA unit protein will fold into four main regions of helix, and it has been speculated that the tertiary structure is as a four-bundle helix protein, similar to other invertebrate carrier proteins (Sheriff et al., 1987). 

Senozan, N. et al. (1981) Hemocyanin of the giant keyhold limpet, Megathura crenulata. In Invertebrate Oxygen Binding Proteins Structure, Active Sites, andFunction (J. Lamy, and J. Lamy, eds.), pp. 703-717. Dekker, New York. 

Lectin affinity chromatography may be used to purify a range of glycoproteins. Lectins are a group of proteins synthesized by plants, vertebrates and a number of invertebrate species. Especially high levels of lectins are produced by a variety of plant seeds. Plant lectins are often termed... 

Stecca, B., Southwood, C. M., Gragerov, A. et al. The evolution of lipophilin genes from invertebrates to tetrapods DM-20 cannot replace proteolipid protein in CNS myelin. /. Neurosci. 20,4002-4010, 2000. 

Co-expression of human tau with the fly homolog of GSK3-P resulted in accelerated neurodegeneration and the formation of tau-immunoreactive inclusions. In contrast to what has been described in FTDP-17 and mouse models of tauopathies, tau-induced neurodegeneration involved programmed cell death. Taken together, it appears that conformationally altered, nonfilamentous human tau protein is neurotoxic in invertebrates. 

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