TY - JOUR
T1 - Differential regulation of select osmoregulatory genes and Na+/K+-ATPase paralogs may contribute to population differences in salinity tolerance in a semi-anadromous fish
AU - Mundy, Paige C.
AU - Jeffries, Ken M.
AU - Fangue, Nann A.
AU - Connon, Richard E.
PY - 2020/2
Y1 - 2020/2
N2 - The Sacramento splittail (Pogonichthys macrolepidotus) is a species of special concern that is native to the San Francisco Estuary, USA. Two genetically distinct populations exist and differ in maximal salinity tolerances. We examined the expression of 12 genes representative of osmoregulatory functions in the gill over a 14 day time course at two different salinities [11 or 14 PSU (Practical Salinity Units)] and revealed that each population showed distinct patterns of gene expression consistent with population differences in response to osmotic regimes. The relatively more salinity-tolerant San Pablo population significantly upregulated nine out of the 12 transcripts investigated on day 1 of 11 PSU salinity exposure in comparison to the day zero freshwater control. Three transcripts (nka1a, nka1b, and mmp13) were differentially expressed between the populations at 7 and 14 days of salinity exposure, suggesting a reduced ability of the relatively salinity-intolerant Central Valley population to recover. Additionally, a phylogenetic analysis of several Sacramento splittail Na+/K+-ATPase α1 sequences resulted in grouping by proposed paralog rather than species, suggesting that different paralogs of this gene may exist. These findings, together with prior research conducted on the Sacramento splittail, suggest that the San Pablo population may be able to preferentially regulate select osmoregulatory genes, including different Na+/K+-ATPase α1 paralogs, to better cope with salinity challenges.
AB - The Sacramento splittail (Pogonichthys macrolepidotus) is a species of special concern that is native to the San Francisco Estuary, USA. Two genetically distinct populations exist and differ in maximal salinity tolerances. We examined the expression of 12 genes representative of osmoregulatory functions in the gill over a 14 day time course at two different salinities [11 or 14 PSU (Practical Salinity Units)] and revealed that each population showed distinct patterns of gene expression consistent with population differences in response to osmotic regimes. The relatively more salinity-tolerant San Pablo population significantly upregulated nine out of the 12 transcripts investigated on day 1 of 11 PSU salinity exposure in comparison to the day zero freshwater control. Three transcripts (nka1a, nka1b, and mmp13) were differentially expressed between the populations at 7 and 14 days of salinity exposure, suggesting a reduced ability of the relatively salinity-intolerant Central Valley population to recover. Additionally, a phylogenetic analysis of several Sacramento splittail Na+/K+-ATPase α1 sequences resulted in grouping by proposed paralog rather than species, suggesting that different paralogs of this gene may exist. These findings, together with prior research conducted on the Sacramento splittail, suggest that the San Pablo population may be able to preferentially regulate select osmoregulatory genes, including different Na+/K+-ATPase α1 paralogs, to better cope with salinity challenges.
KW - Estuary
KW - mRNA abundance
KW - Osmoregulation
KW - Pogonichthys macrolepidotus
KW - Sacramento splittail
KW - Stress
UR - http://www.scopus.com/inward/record.url?scp=85074650589&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85074650589&partnerID=8YFLogxK
U2 - 10.1016/j.cbpa.2019.110584
DO - 10.1016/j.cbpa.2019.110584
M3 - Article
C2 - 31676412
AN - SCOPUS:85074650589
VL - 240
JO - Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
JF - Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
SN - 1095-6433
M1 - 110584
ER -