Fig 1.
Cultures of sturgeon epidermal cells.
(A) Sheet of epithelial cells expanding outward from explant of white sturgeon skin (at bottom of panel). (B) Colony of green sturgeon epidermal cells in primary culture surrounded by sparse 3T3 feeder layer cells. (C) Squame-like cells remaining attached to dish after treatment of confluent culture of white sturgeon cells with ionophore X537A overnight followed by SDS + DTT.
Fig 2.
(A) Passage 3 white sturgeon epidermal cells confluent for a week and (B) confluent human dermal fibroblasts were trypsinized, suspended in saline and analyzed electronically using a Multisizer 3 Coulter counter adapted for measurement of cell sizes.
Table 1.
Cross-linked envelope formation.
Table 2.
Percent identities in TGM1 sequences generated from two-way comparisons using NCBI Protein BLAST.
Table 3.
Cysteine clusters in sturgeon (white, green, sterlet) compared to representative teleost, amphibians, reptiles and mammals.
Fig 3.
Relative expression levels of TGM1 A and B determined by real time PCR.
(A) RNA was isolated from the indicated passages of cells from a single sturgeon. (B) The average ratio TGM1A/TGM1B in panel A is shown along with the ratios for two other octoploid (8N) white sturgeon (lighter shading), a dodecaploid white sturgeon (12N, dark shading) and a green sturgeon (as labeled). Error bars indicate values derived from 2 or 3 independent cultures except for P3 (7 cultures).
Fig 4.
Human and sturgeon epidermal cell responses to TCDD.
Human (A, B) and sturgeon (C, D) epidermal cells were pre-treated with indicated concentrations of AHR inhibitors (CH223191 or GNF351) 1 hr before TCDD exposure. After overnight incubation, the cells were treated with 7-ethoxyresorufin in serum free medium for 2 hr and the medium was harvested for EROD assay performed as described in the Methods. The CYP1A activity was corrected for background activity measured from fresh medium containing 7-ethoxyresorufin and expressed as a percent of the CYP1A activity obtained from cells treated with TCDD (set to 100%). Results are presented as the mean ± SD of three independent experiments. Significant differences from untreated control were calculated (one-way ANOVA and Dunnett’s post hoc test) with GraphPad Prism 9 (ns, not significant different; **, p < 0.01; ****, p < 0.0001).