DOI: 10.5061/dryad.4b8gtht8v
title: Data from: Cold-acclimation increases depolarization resistance and tolerance in muscle fibers from a chill-susceptible insect, Locusta migratoria

description: Cold exposure depolarizes cells in insects due to a reduced electrogenic
 ion transport and a gradual increase in extracellular [K+]. Cold-induced
 depolarization is linked to cold injury in chill-susceptible insects, and
 the locust, Locusta migratoria, has shown improved cold tolerance
 following cold-acclimation through depolarization resistance. Here we
 investigate how cold-acclimation influences depolarization resistance and
 how this resistance relates to improved cold tolerance. To address this
 question, we investigated if cold-acclimation affects the electrogenic
 transport capacity and/or the relative K+ permeability during cold
 exposure by measuring membrane potentials of warm- and cold-acclimated
 locusts in the presence/absence of ouabain (Na+/K+ pump blocker) or
 4-aminopyridine (4-AP, voltage-gated K+ channel blocker). In addition, we
 compared the membrane lipid composition of muscle tissue from warm- and
 cold-acclimated locust, and the abundance of a range transcripts related
 to ion transport and cell injury accumulation. We found that
 cold-acclimated locusts are depolarization resistant due to an elevated K+
 permeability, facilitated by opening of 4-AP sensitive K+ channels. In
 accordance, cold-acclimation was associated with an increased abundance of
 shaker transcripts (gene encoding 4-AP sensitive voltage-gated K+
 channels). Furthermore, we found that cold-acclimation improved muscle
 cell viability following exposure to cold and hyperkalemia even when
 muscles were depolarized substantially. Thus, cold-acclimation confers
 resistance to depolarization by altering the relative ion permeability,
 but cold-acclimated locusts are also more tolerant to depolarization.
description: Methods are described in the associated article
description: <b>Table S1
 –</b> <b>List of primers and their sequences.</b> All
 primers were created based on sequences from the L. migratoria genome.
 Primers marked with <sup>1</sup> are primers based on
 unannotated transcripts where annotation was inferred by looking for
 homologues in the Drosophila melanogaster genome. All other primers are
 based on annotated transcripts in the L. migratoria genome. <b>Table
 S1 –</b> <b>List of primers and their sequences.</b> All
 primers were created based on sequences from the L. migratoria genome.
 Primers marked with <sup>1</sup> are primers based on
 unannotated transcripts where annotation was inferred by looking for
 homologues in the Drosophila melanogaster genome. All other primers are
 based on annotated transcripts in the L. migratoria genome.
 <b>Table S2 –
 Transcription abundance (TA) from warm- (WA) or cold-acclimated (CA)
 locusts.</b> The transcription abundance is presented in the format
 1-2-4 days of acclimation and displayed as transcription relative to the
 common average (both sexes combined) transcription level for locusts
 acclimated under warm conditions for 1 day. For the transcripts marked
 with <sup>u</sup>, their primers promoted unspecific/uneven
 amplification. AS, AD or S represent significant effects of acclimation
 status (AS), acclimation duration (AD) or sex (S) and x denotes a
 significant interaction between two effects. Statistical analysis was done
 as 3-way ANOVAs, N was 4/5/2 (WA 1/2/4 days, males), 8/7/5 (CA 1/2/4 days
 males), 12/5/5 (WA 1/2/4, females), or 13/11/6 (CA 1/2/4 , females)
 animals. <b>Table S3</b>
 <b>– Analysis of lipid content of muscles from warm- (WA) or
 cold-acclimated (CA) locusts.</b> The lipids are named by their head
 group with chain length and number of saturated bonds in the parenthesis.
 The head groups are: FA (fatty acyl), lysophosphatidylcholine (LPC),
 lysophosphatidylethanolamine (LPE), phosphatidylcholine (PC),
 phosphatidylethanolamine (PE), phosphatidylglycerol (PG),
 phosphatidylinositol (PI), phosphatidylserine (Pser), sphingomyelin (SM)
 and cardiolipin (CL). The p-values reported are calculated from a 2-tailed
 student’s t-test. To be considered significant, p-values must be less than
 the corresponding threshold calculated using the holm-bonferroni method.
 Lipids with a p-value below their threshold for statistical significance
 are marked with bold font.