Temperature-dependent activity of kinesins is regulable

AbstractSeasonal and daily activity of three carpenter ants, Camponotus herculeanus, C. noveboracensis and C. pennsylvanicus in northwestern Ontario, was measured by counting the ants moving along underground trails. The start of seasonal activity was temperature dependent. Activity peaked in June and early July, corresponding to the period of rapid larval growth, and thereafter declined independently of temperature, ceasing in early October. Few ants (between 4 and 6%) carried visible objects. Daily activity was correlated with temperatures in early June, with the peak in mid-afternoon. However, as the season progressed activity extended further into the night, C. pennsylvanicus becoming virtually nocturnal. Temperatures inside the nest during larval development were raised as much as 16 °C above normal, presumably by metabolic heat from the ants.

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Temperature-dependent activity of brackish water yellow eels, Anguilla anguilla L.

Aquaculture Research ◽

10.1111/j.1365-2109.1986.tb00103.x ◽

1986 ◽

Vol 17 (3) ◽

pp. 201-205 ◽

Cited By ~ 1

Author(s):

L. A. VØLLESTAD

Keyword(s):

Brackish Water ◽

Anguilla Anguilla ◽

Temperature Dependent ◽

Dependent Activity ◽

Yellow Eels

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Microarray-based screening system identifies temperature-controlled activity of Connexin 26 that is distorted by mutations

Scientific Reports ◽

10.1038/s41598-019-49423-3 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Hongling Wang ◽

Frank Stahl ◽

Thomas Scheper ◽

Melanie Steffens ◽

Athanasia Warnecke ◽

...

Keyword(s):

Lucifer Yellow ◽

Point Mutations ◽

Salt Bridge ◽

Connexin 26 ◽

Temperature Sensitive ◽

Temperature Dependent ◽

Dependent Activity ◽

Electrode Voltage ◽

Uptake Assay ◽

Weak Activity

Abstract Here, we show that human Connexin 26 (hCx26 or Cx26WT) hemichannel opening rapidly enables the transport of small molecules when triggered by temperature and by compensation of the Ca2+ blockade with EDTA. Point mutations within Cx26 were analysed by a novel optical microarray-based Lucifer Yellow uptake assay or by two electrode voltage clamp (TEVC) on frog oocytes to monitor simultaneous activities of channel proteins. Point mutations L90P, F161S, R184P or K188N influenced the temperature-dependent activity drastically. Since several mutations blocked trafficking, the temperature-dependent activity of the recombinant synthesized and purified wild-type Cx26WT and Cx26K188N hemichannel was tested by liposome flux assay (LFA) and on a microarray-based Lucifer Yellow uptake assay under warm conditions (>30 °C). The data from TEVC measurements and dye flux experiments showed that the mutations gave no or only a weak activity at increased temperature (>30 °C). We conclude that the position K188 in the Cx26WT forms a temperature-sensitive salt bridge with E47 whereas the exchange to K188N destabilizes the network loop- gating filter, which was recently identified as a part of the flexible Ca2+ binding site. We assume that the temperature sensitivity of Cx26 is required to protect cells from uncontrolled release or uptake activities through Cx26 hemichannels.

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