Genes differentially expressed between ecotypes (comp 3 and 4)
In contrast 3 we only discuss differences between the two controls
(Figure 2). Genes that were upregulated in SwC compared to FwC included
the Sarcoplasmic/endoplasmic reticulum calcium ATPase 1 (ATP2a1 ),
an enzyme that catalyzes the hydrolysis of ATP with the translocation of
calcium from the cytosol to the sarcoplasmic reticulum lumen; several
stress-related cytochrome P450 (CYP1a (also overlapping with
contrast 1 and 2), CYP1c1, CYP1c2, CYP2y3, CYP7a1 ), seven genes
in the solute carrier family (including SLC16a1b ), one myosin
(myh11a ), where the class XI myosins are associated with various
organelles/vesicles (Tian et al. 2021). Genes upregulated in FwC
compared to SwC included Aquaporin 3a (AQ P3a), several ATP’s
(ATP6V0C, ATP6V0C, ATP6v1d, AP6v1e1b ; Figure 7 ),
arrestin domain containing 2 (arrdc2 ), 11 solute carriers, and
prolactin Receptor type a (PRLRa ) had a higher expression in
freshwater, and a slight regulation within saltwater, as SwFw had lower
expression than SwC (Figure 6c) .
Of the 502 apparently transcripts that had similar expression within
ecotype despite salinity change, 173 had a higher expression in the
saltwater ecotype, and included one gene linked to ATP-transport, ATPase
phospholipid transporting (ATP8a2 ), two linked to calcium
transport; calcium channel, voltage-dependent (cacnb1 ,Figure 6d ) and anoctamin 1, calcium activated chloride channel
(ano1 , Figure 6b ), NADPH oxidase 1 (nox1 ), one
solute carriers (SLC6a1like ), interleukin 11 receptor
(IL11ra ) and genes linked to tyrosine kinase proteins, which in
turn has been found to function as activators of several ion-pumps;
protein kinase 7 (PTK7 ), protein tyrosine phosphatase-
non-receptor (PTPN14 ) and receptor type (PTPrfa ), and
erb-b2 receptor tyrosine kinase 3b (erbb3b ). A total of 329
transcripts had a higher expression in the freshwater ecotype, and
included several ATP’s (ATP6V0e1, ATP6V1A, ATP6V1c1a, ATP6V1f ,Figure 7 ), where one is involved in T-cell regulation
(tcirg1a ); four annexin genes, which are linked to salinity
stress in plants (ANXAa1, ANXA3b, ANXA5b (Figure 6d ) andANXA11b ), two linked to calcium: calcium homeostasis modulator
family (calhm5.2 ) and mitochondrial calcium uptake (micu2 )
and one stress-related UDP-glucose (ugp2b ). The freshwater
ecotype also had a higher expression of claudins (cldn1, cldn7b,
cldnf) and occludins (oclnb ), proteins that are involved with
tight junctions and reduction of ion efflux from the cells.