+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

ATCase activity, RNA:DNA ratio, gonad development stage, and egg production in the female copepod Calanus helgolandicus

, : ATCase activity, RNA:DNA ratio, gonad development stage, and egg production in the female copepod Calanus helgolandicus. Marine Biology (Berlin) 135(1): 1-10, Oct

Some investigators have proposed the measurement of aspartate transcarbamylase (ATCase) activity as a suitable technique for estimating zooplankton productivity. However, this technique has never been comprehensively evaluated under controlled laboratory conditions nor compared extensively with other productivity techniques in the field. This paper describes such an evaluation, using the reproduction of the calanoid copepod Calanus helgolandicus as an index of germinal growth, an important aspect of zooplankton productivity. ATCase activity and RNA:DNA ratio both increased significantly with increasing gonad maturation. In addition, ATCase activity in females responded immediately to changing food conditions, whilst changes in egg production lagged behind by apprxeq 24 h. Shifting the ATCase data by 24 h revealed a significant and positive correlation of ATCase activity with egg production. However, in well-fed females, ATCase activity assayed at constant temperature was apparently independent of environmental temperature conditions, whilst egg production was temperature-dependent. In the field, ATCase activity was significantly correlated with egg production only in autumn and winter; when a complete seasonal cycle was considered, no correlation was found between the two measurements. These findings suggest that ATCase is involved partially in either germinal growth and/or in other biosynthetic processes of female C. helgolandicus; thus, ATCase activity does not reflect copepod egg-production with any certainty.


DOI: 10.1007/s002270050595

Other references

Podboronov, V.M.; Petropavlovskaia, I.S., 1970: Effect of acrichine on the development of penicillin resistant staphylococci. Antibiotiki 15(6): 526-528

Anonymous, 1978: Violence to children. Health Visitor 51(5): 167-167

Xiu Lan.; Jingming Wei., 1991: On the evolution of the West Tarim Gulf based on Late Cretaceous-Early Tertiary bivalve faunas. Unknown

Ghoorchian, A.; Vandemark, K.; Freeman, K.; Kambow, S.; Holland, N.B.; Streletzky, K.A., 2014: Size and shape characterization of thermoreversible micelles of three-armed star elastin-like polypeptides. Three-armed star elastin-like polypeptides are shown to have the capability of self-assembling into micellar constructs at certain environmental conditions. Here, a study of the size distribution, shape, and molecular weight of these micelles at d...

Odstrcil, M.; Baksh, P.; Boden, S.A.; Card, R.; Chad, J.E.; Frey, J.G.; Brocklesby, W.S., 2016: Ptychographic coherent diffractive imaging with orthogonal probe relaxation. Ptychography is a scanning coherent diffractive imaging (CDI) technique that relies upon a high level of stability of the illumination during the course of an experiment. This is particularly an issue for coherent short wavelength sources, where t...

Porter J.B.; Gyparaki M.; Huehns E.R.; Hider R.C., 1986: The relationship between lipophilicity of hydroxypyrid 4 one iron chelators and cellular iron mobilization using an hepatocyte culture model. Biochemical Society Transactions 14(6): 1180

Tingey, D.C., 1961: Control of Roemeria poppy in winter wheat. Data from these experiments indicate that a fairly high rate (2. 67 lb. acid equivalent) of an ester of 2,4-D, applied at or before the bloom stage, was required to prevent Roemeria poppy (Roemeria refracta) from producing seed. Even though good p...

Zimmermann, G., 1937: Beitrage zum funktionellen Bau der harten Hirnhaut. Matematikai es Termeszettudomanyi Ertesito (Budapest): 56: 262-286

Ashkar, A.A.; Mossman, K.L.; Coombes, B.K.; Gyles, C.L.; Mackenzie, R., 2008: FimH adhesin of type 1 fimbriae is a potent inducer of innate antimicrobial responses which requires TLR4 and type 1 interferon signalling. Components of bacteria have been shown to induce innate antiviral immunity via Toll-like receptors (TLRs). We have recently shown that FimH, the adhesin portion of type 1 fimbria, can induce the innate immune system via TLR4. Here we report that F...

Crosato, M.; Crua, G., 1968: On the action of a preparation of lyophilized pancreas in some digestive insufficiencies in childhood. Minerva Pediatrica 20(11): 613-614