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Kocáb O, Bačovčinová M, Bokor B, Šebela M, Lenobel R, Schöner CR, Schöner MG, Pavlovič A. Enzyme activities in two sister-species of carnivorous pitcher plants (Nepenthes) with contrasting nutrient sequestration strategies. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 161:113-121. [PMID: 33581619 DOI: 10.1016/j.plaphy.2021.01.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/31/2021] [Indexed: 06/12/2023]
Abstract
The carnivorous pitcher plants of the genus Nepenthes usually attract, capture and digest arthropod prey to obtain mineral nutrients. But few members of the genus have evolved specialized nutrient sequestration strategies to acquire nitrogen from the faeces and urine of mutualistic mammals, which they attract. Because the plants obtain significant amounts of nitrogen in a more available form, we hypothesized that they have relaxed the production of digestive enzymes. If so, species that digest mammal faeces should show fewer digestive enzymes than closely related species that rely on arthropods. We tested this hypothesis by comparing digestive enzymes in 1) Nepenthes hemsleyana, whose pitchers serve as roosts for the mutualistic woolly bat Kerivoula hardwickii, which also defecate inside the pitchers, and 2) the close relative Nepenthes rafflesiana, a typical arthropod capturing species. To investigate the dynamics of aspartic proteases (nepenthesin I and II) and type III and IV chitinases in both species, we conducted qPCR, western blotting, mass spectrometry, and enzyme activity measurements. We found that mRNA in pitcher tissue and enzyme abundance in the digestive fluid is upregulated in both species in response to faeces and insect feeding. Contrary to our initial hypothesis, the final nepenthesin proteolytic activity in the digestive fluid is higher in response to faeces addition than to insect prey irrespective of Nepenthes species. This indicates that faeces can mimic arthropod prey triggering the production of digestive enzymes and N. hemsleyana retained capacity for production of them.
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Affiliation(s)
- Ondřej Kocáb
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic
| | - Michaela Bačovčinová
- Department of Botany, Institute of Biology and Ecology, Šafárik University, Mánesova 23, SK-040 01, Košice, Slovakia
| | - Boris Bokor
- Department of Plant Physiology, Faculty of Natural Sciences, Comenius University in Bratislava, Ilkovičova 6, Mlynská Dolina B2, SK-842 15, Bratislava, Slovakia; Comenius University Science Park, Comenius University in Bratislava, Ilkovičova 8, SK-841 04, Bratislava, Slovakia
| | - Marek Šebela
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic
| | - René Lenobel
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic
| | - Caroline R Schöner
- Zoological Institute and Museum, University of Greifswald, Loitzer Straße 26, 17489, Greifswald, Germany
| | - Michael G Schöner
- Zoological Institute and Museum, University of Greifswald, Loitzer Straße 26, 17489, Greifswald, Germany
| | - Andrej Pavlovič
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, CZ-783 71, Olomouc, Czech Republic.
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