Plants make a variety of specialized metabolites that can mediate interactions with animals, microbes, and competitor plants. Understanding how plants synthesize these compounds enables studies of their biological roles by manipulating their synthesis in vivo as well as producing them in vitro. Acylsugars are a group of protective metabolites that accumulate in the trichomes of many Solanaceae family plants. Acylinositol biosynthesis is of interest because it appears to be restricted to a subgroup of species within the Solanum genus. Previous work characterized a triacylinositol acetyltransferase involved in acylinositol biosynthesis in the Andean fruit plant
The retrocerebral organ (RCO) is a complex glandular system that is widely distributed across species of phylum Rotifera (sensu stricto). This system is hypothesized to secrete mucus that aids in benthic locomotion, adhesion, and/or reproduction. Unfortunately, the ultrastructure of the RCO is mostly unknown, having only been partially examined in one species. We used transmission electron microscopy and confocal laser scanning microscopy to describe the RCO in the planktonic freshwater rotifer
- PAR ID:
- 10402417
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Invertebrate Biology
- Volume:
- 142
- Issue:
- 1
- ISSN:
- 1077-8306
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract (lulo or naranjilla). We characterized three additionalSolanum quitoense trichome expressed enzymes and found that virus‐induced gene silencing of each caused changes in acylinositol accumulation. pH was shown to influence the stability and rearrangement of the product of ASAT1H and could potentially play a role in acylinositol biosynthesis. Surprisingly, the in vitro triacylinositol products of these enzymes are distinct from those that accumulateS. quitoense in planta . This suggests that additional enzymes are required in acylinositol biosynthesis. These characterized enzymes, nonetheless, provide opportunities to test the biological impact and properties of these triacylinositols in vitro.S. quitoense -
Abstract Rotifers are aquatic microinvertebrates that live in the plankton or in the benthos, which may include a variety of macrophytes. Among these periphytic forms of rotifers, some have taken up a sessile existence and secrete protective tubes around their bodies. One type of tube common to species of
Floscularia is made of small round pellets. To date, the building process and some fine structural details are known forFloscularia ringens , but many questions about the composition of the tube and its ultrastructure still remain unanswered. Here, we use transmission electron microscopy and scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM –EDS ) to study the ultrastructure of the pellets and their elemental composition, respectively, in the putative sister species,Floscularia conifera . We revealed several new details that add important information about the physiology of tube‐making in species ofFloscularia . First, we note an inner secretory membrane that is thin, electron lucent, and supports the external pellets. The pellets are relatively consistent in size and have a small depression on their inner surface. All pellets are individually wrapped in a secretory membrane that completely encapsulates suspended materials collected from the surrounding water. Elemental signatures of pellets reveal they consist mostly of carbon (C), nitrogen (N), and oxygen (O), with some silicon (Si) content that is likely the result of diatom shells. Other trace elements such as iron (Fe) and sodium (Na) are also present and likely the result of incorporated bacteria and suspended materials. When larval rotifers are cultured in filtered pond water, the pellets consist mostly of C and O, with little N and no Si; Fe is present in smaller amounts. These new discoveries provide a better understanding of the physiology of rotifer tube construction and tube composition, and their future utility in understanding if and how changes in freshwater environments might impact these factors. -
Abstract Female reproduction in squamate reptiles (lizards and snakes) is highly diverse and mode of reproduction, clutch size, and reproductive tract morphology all vary widely across this group of ~11,000 species. Recently, CRISPR genome editing techniques that require manipulation of the female reproductive anatomy have been developed in this group, making a more complete understanding of this anatomy essential. We describe the adult female reproductive anatomy of the model reptile the brown anole (
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Abstract Rotifers possess complex morphologies despite their microscopic size and simple appearance. Part of this complexity is hidden in the structure of their organs, which may be cellular or syncytial. Surprisingly, organs that are cellular in one taxon can be syncytial in another. Pedal glands are widespread across Rotifera and function in substrate attachment and/or egg brooding. These glands are normally absent in
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