DOI: 10.5061/dryad.q4q52
title: Data from: Cell turnover and detritus production in marine sponges from tropical and temperate benthic ecosystems

description: This study describes in vivo cell turnover (the balance between cell
 proliferation and cell loss) in eight marine sponge species from tropical
 coral reef, mangrove and temperate Mediterranean reef ecosystems. Cell
 proliferation was determined through the incorporation of
 5-bromo-2′-deoxyuridine (BrdU) and measuring the percentage of
 BrdU-positive cells after 6 h of continuous labeling (10 h for Chondrosia
 reniformis). Apoptosis was identified using an antibody against active
 caspase-3. Cell loss through shedding was studied quantitatively by
 collecting and weighing sponge-expelled detritus and qualitatively by
 light microscopy of sponge tissue and detritus. All species investigated
 displayed substantial cell proliferation, predominantly in the choanoderm,
 but also in the mesohyl. The majority of coral reef species (five) showed
 between 16.1±15.9% and 19.0±2.0% choanocyte proliferation (mean±SD) after
 6 h and the Mediterranean species, C. reniformis, showed 16.6±3.2% after
 10 h BrdU-labeling. Monanchora arbuscula showed lower choanocyte
 proliferation (8.1±3.7%), whereas the mangrove species Mycale
 microsigmatosa showed relatively higher levels of choanocyte proliferation
 (70.5±6.6%). Choanocyte proliferation in Haliclona vansoesti was variable
 (2.8–73.1%). Apoptosis was negligible and not the primary mechanism of
 cell loss involved in cell turnover. All species investigated produced
 significant amounts of detritus (2.5–18% detritus bodyweight−1·d−1) and
 cell shedding was observed in seven out of eight species. The amount of
 shed cells observed in histological sections may be related to differences
 in residence time of detritus within canals. Detritus production could not
 be directly linked to cell shedding due to the degraded nature of expelled
 cellular debris. We have demonstrated that under steady-state conditions,
 cell turnover through cell proliferation and cell shedding are common
 processes to maintain tissue homeostasis in a variety of sponge species
 from different ecosystems. Cell turnover is hypothesized to be the main
 underlying mechanism producing sponge-derived detritus, a major trophic
 resource transferred through sponges in benthic ecosystems, such as coral
 reefs.
description: Proliferation difference
 r fileR scripts for percentage
 of proliferating choanocyte and mesohyl cells per
 individual.prolif_diff.rDifference in the percentage proliferation in choanocytes and mesohyl cellsPercentage of proliferating choanocyte and mesohyl cells per individual and per speciesprolif_diff.csvHalisarca caerulea choanocyte proliferation 6h vs 10hPercentage of proliferating choanocytes in Halisarca caerulea specimens, incubated with BrdU for either 6 hours or 10 hours.prolif_6vs10.csvHalisarca caerulea choanocyte proliferation 6h vs 10h r scriptR script for percentage of proliferating choanocytes in Halisarca caerulea specimens, incubated with BrdU for either 6 hours or 10 hours.prolif_6vs10.rDetritus productionDaily detritus production (in mg) for test and control samples, for several sponge species and (for most individuals) sampling over timedetritus_prod.csvDetritus production R scriptR script for daily detritus production (in mg) for test and control samples, for several species and (for most individuals) sampling over timedetritus_prod.rDetritus production vs shedder typeDaily detritus production as percentage of body weight for various sponge species and shedder types.detritus_shed.csvDetritus production vs shedder type R scriptR script for daily detritus production as percentage of body weight for various species and shedder types.detritus_shed.r