Freshwater snail aquaporin 4 shows water-selective transport and temperature-dependent expression

A laboratory study of the freshwater gastropod Pomacea canaliculata found that its aquaporin 4 protein, PcAqp4L, increased osmotic water permeability in Xenopus laevis oocytes while showing no detectable transport of glycerol or other tested solutes. The abstract describes PcAqp4L as a structurally atypical but water-selective channel, with an atypical NPA/NPI pore motif and a distinctive V–V–G–R aromatic/arginine constriction.

Researchers combined sequence and structural analysis with functional assays in oocytes, transcriptional measurements under cold and heat stress, and mass spectrometry. The oocyte experiments provided the functional evidence for water transport, whereas the expression results showed that PcAqp4L transcription was upregulated under cold conditions and downregulated under heat conditions. Mass spectrometry also identified endogenous PcAqp4L-specific peptides, providing evidence that the protein was expressed in the gastropod.

Together, the reported observations associate PcAqp4L with temperature-responsive changes in water balance. The study links the channel’s sequence-derived structural features, measured transport activity and stress-associated transcriptional response, but the evidence available in the abstract does not establish that PcAqp4L directly causes whole-animal changes in osmoregulation, survival, stress tolerance or ecological performance. The functional findings were obtained in an animal-cell model rather than in intact snails, and the abstract does not provide the experimental durations, sample sizes, effect sizes or statistical details needed to assess those limits more precisely.

This was an animal and cell study focused on one aquaporin from a freshwater invertebrate. Its broader contribution is to extend knowledge of aquaporin structural diversity in mollusks while suggesting a role for PcAqp4L in temperature-related osmotic regulation. That role remains a mechanistic implication of the combined structural, expression and transport results rather than a demonstrated organism-level outcome.

Subject of Research: Structure, water transport and temperature-responsive expression of PcAqp4L in the freshwater gastropod Pomacea canaliculata

Article Title: Structural and functional characterization of aquaporin 4 from the freshwater gastropod Pomacea canaliculata under temperature stress

Article References: Wei, R., Lu, M.-X., Chang, Y.-W., Wu, C.-D., Xie, H.-F., Zha, G.-X., Hu, J., & Du, Y.-Z. (2026). Structural and functional characterization of aquaporin 4 from the freshwater gastropod Pomacea canaliculata under temperature stress. Molecular Biology Reports, 53(1), Article 1579. https://doi.org/10.1007/s11033-026-12753-3

Image Credits: AI Generated

DOI: 10.1007/s11033-026-12753-3

Keywords: Pomacea canaliculata, aquaporin 4, PcAqp4L, water transport, temperature stress, osmoregulation, Xenopus oocytes, gene expression, mass spectrometry, molluscan physiology, Structural, functional