Lectins and Tetrahymena – A review

Abstract

The unicellular ciliate Tetrahymena is a complete organism, one of the most highly developed protozoans, which has specialized organelles performing each of the functions characteristic to the cells of higher ranked animals. It is also able to produce, store, and secrete hormones of higher ranked animals and also react to them. It produces lectins that can bind them and has functions, which are influenced by exogenous lectins. The review lists the observations on the relationship between lectins and Tetrahymena and try to construe them on the basis of the data, which are at our disposal. Considering the data, lectins can be used by Tetrahymena as materials for influencing conjugation, for stimulating hormone receptors, and by this, mimic the hormonal functions. Lectins can influence phagocytosis and movement of the cells as well as the cell division. As Tetrahymena can recognize both related and hostile cells by the help of lectins and surface sugars, it could be surmised a complex predator-prey system. This could determine the survival of the population as well as the nourishment conditions. When Tetrahymena is pathogenic, it can use lectins as virulence factors.

Tailed giant Tupanvirus possesses the most complete translational apparatus of the known virosphere

“…Surprisingly, we observed four distinct profiles of infectiveness: (i) productive cycle in permissive cells; (ii) abortive cycle; (iii) refractory cells; and (iv) most surprisingly, non-host cells exhibiting a cytotoxic phenotype in the presence of Tupanvirus without multiplication, a circumstance never previously reported—to the best of our knowledge (Supplementary table 1 ; Supplementary Notes 1). This latter profile was intriguing because toxicity was observed in Tetrahymena sp., a ravenous free-living protist 26 . This unusual phenotype was also observed in A. castellanii but only at higher multiplicities of infection (50 and 100; Fig.…”

Is there a hormonal regulation of phagocytosis at unicellular and multicellular levels? A critical review

“…However, hormones are synthesized, stored, and secreted by unicells which can influence phagocytosis [99,100] and there is a similar situation in multicells, where hormones which has specific functions (e.g., regulation of sugar metabolism, blood calcium level, ovarian cycle, etc.) are also influencing the phagocytosis of professional cells (macrophages and neutrophil granulocytes).…”

The Protozoan Tetrahymena: Cellular Model for Biological Studies

“…A recent study has shown that Tetrahymena is able to use lectins to influence sexual reproduction, stimulate hormonal receptors, imitate hormonal functions, influence phagocytosis, cell movement and cell division [68]. Lectins are proteins found in plants and animals and are used to diagnose sugars in solutions or on the surface of cells, as well as in the study of blood groups.…”