The brine shrimps have evolved to express sodium pumps that exchange 2 Na+ for 1 K+ (instead of the canonical 3Na+ for 2 K+). This adaptation helps Artemia remove proportionally higher amount of sodium to the exterior which enable this animal build and maintain larger Na+ gradients imposed by highly saline maji.
Uduvi wa brine (Artemia) wa subphylum Crustacea huishi katika chumvi nyingi. maji. Hawa ni wanyama tu wanaojulikana kustawi katika viwango vya sodiamu zaidi ya 4 M.
Wanawezaje kushinda hali hizo ngumu?
Watafiti wamegundua kuwa uvumbuzi wa kibayolojia unasaidia brine uduvi kukabiliana na mazingira ya mkusanyiko wa chumvi nyingi.
ATPase iliyoko kwenye utando wa plasma ya nje ya seli hufanya kama pampu ya sodiamu-potasiamu kutoa chumvi muhimu ili kudumisha usawa wa chumvi. Kwa kawaida, kwa kila ATP inayotumiwa, hii [km. Na+, K+ -ATPase (NKA) pampu] huondoa Na+ 3 kutoka kwenye seli na kuingiza 2K+ hiyo kwenye seli.
However, the brine shrimps have evolved to express sodium pumps that exchange 2 Na+ for 1 K+ (instead of the canonical 3Na+ for 2 K+). This adaptation helps Artemia remove proportionally higher amount of sodium to the exterior which enable this animal build and maintain larger Na+ gradients imposed by highly saline maji.
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Reference:
Artigas P. et al 2023. Pampu Na yenye stoichiometry iliyopunguzwa inadhibitiwa na uduvi wa brine katika hali ya chumvi nyingi. PNAS. 11 Desemba 2023 .120 (52) e2313999120. DOI: https://doi.org/10.1073/pnas.2313999120
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