Ribosome‐inactivating lectins with polynucleotide:adenosine glycosidase activity

Battelli, Maria Giulia; Barbieri, Luigi; Bolognesi, Andrea; Buonamici, Laura; Valbonesi, Paola; Polito, Letizia; Damme, Els J.M. Van; Peumans, Willy J.; Stirpe, Fiorenzo

doi:10.1016/s0014-5793(97)00463-8

Cited by 36 publications

(27 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This complete lack of PAG activity for SNA‐I is most probably due to its intrinsically lower enzymatic activity. As previously shown, SNA‐I exhibits a markedly lower PAG activity on different nucleic acid substrates than other type‐2 RIPs (possibly as a result of its complex tetrameric structure) [35,36]. As none of the elderberry RIPs display enzymatic activity towards plant ribosomes in rRNA N ‐glycosylase activity assays [9], they are ideal candidates for assessing whether the PAG activity is involved in RIP‐mediated protection.…”

Section: Pag Activity Towards Tmv Genomic Rnamentioning

confidence: 99%

Analysis of the in planta antiviral activity of elderberry ribosome‐inactivating proteins

Vandenbussche

Desmyter

Ciani

et al. 2004

European Journal of Biochemistry

View full text Add to dashboard Cite

Although the type-2 ribosome-inactivating proteins (SNA-I, SNA-V, SNLRP) from elderberry (Sambucus nigra L.) are all devoid of rRNA N-glycosylase activity towards plant ribosomes, some of them clearly show polynucleotideadenosine glycosylase activity towards tobacco mosaic virus RNA. This particular substrate specificity was exploited to further unravel the mechanism underlying the in planta antiviral activity of ribosome-inactivating proteins. Transgenic tobacco (Nicotiana tabacum L. cv Samsun NN) plants expressing the elderberry ribosome-inactivating proteins were generated and challenged with tobacco mosaic virus in order to analyze their antiviral properties. Although some transgenic plants clearly showed antiviral activity, no clear correlation was observed between in planta antiviral activity of transgenic tobacco lines expressing the different ribosomeinactivating proteins and the in vitro polynucleotideadenosine glycosylase activity of the respective proteins towards tobacco mosaic virus genomic RNA. However, our results suggest that the in planta antiviral activity of some ribosome-inactivating proteins may rely on a direct mechanism on the virus. In addition, it is evident that the working mechanism proposed for pokeweed antiviral protein cannot be extrapolated to elderberry ribosome-inactivating proteins because the expression of SNA-V is not accompanied by induction of pathogenesis-related proteins.Keywords: elderberry; polynucleotide-adenosine glycosylase activity; ribosome-inactivating protein; Sambucus nigra; viral protection.Ribosome-inactivating proteins (RIPs; EC 3.2.2.22) are a heterogeneous family of structurally and evolutionary related plant proteins sharing a common functional domain that catalytically removes a specific adenine residue from a highly conserved, surface-exposed stem-loop structure found in the large rRNA of prokaryotic and eukaryotic ribosomes [1,2]. At present, they are subdivided on the basis of the structure of the genes and the corresponding proteins into holo-RIPs and chimero-RIPs [3]. Whereas holo-RIPs consist exclusively of a single catalytically active protomer of either one (classical type-1 RIPs) or two smaller polypeptide chains (e.g. maize RIP b-32), chimero-RIPs are built up of chimeric protomers with an N-terminal catalytically active domain arranged in tandem with a structurally and functionally unrelated C-terminal domain (classical type-2 and type-3 RIPs).Biochemical and molecular studies have shown that the elderberry tree expresses a complex mixture of type-2 RIPs and/or lectins in virtually all tissues. In agreement with the chronological order of their discovery, these Sambucus nigra agglutinins (SNAs) are numbered SNA-I to SNA-V. The first elderberry lectin was identified in bark tissue and described as a NeuAc(a-2,6)Gal/GalNAc-specific agglutinin (called SNA-I) [4,5]. Although already discovered in 1984, SNA-I was recognized as a type-2 RIP only when the corresponding gene was cloned in 1996 [6]. Besides SNA-I, elderberry bark contains a second NeuAc(...

show abstract

Section: Pag Activity Towards Tmv Genomic Rnamentioning

confidence: 99%

Analysis of the in planta antiviral activity of elderberry ribosome‐inactivating proteins

Vandenbussche

Desmyter

Ciani

et al. 2004

European Journal of Biochemistry

View full text Add to dashboard Cite

show abstract

“…These results led to the suggestion that nigrin b has a low cytotoxicity because the majority of the RIP was degraded by cells and its intracellular routeing did not include passage through the TGN. A very low binding to the cell membrane was associated with a low cytotoxicity in the case of IRA, a type 2 RIP from Iris, which has an IC 50 for HeLa cells of 1.34 ¥ 10 -7 M [28]. Also in the case of ebulin l, one of the type 2 RIPs from Sambucus, the negligible cytotoxicity (IC 50 for HeLa cells 6.2 ¥ 10 -8 M [29]) was attributed to a reduced affinity of its lectin B chain for galactosides compared to the ricin B chain [30].…”

mentioning

confidence: 99%

Interaction of volkensin with HeLa cells: binding, uptake, intracellular localization, degradation and exocytosis

Battelli

Musiani

Buonamici

et al. 2004

Cell. Mol. Life Sci.

View full text Add to dashboard Cite

Among two-chain ribosome-inactivating proteins (RIPs), volkensin is the most toxic to cells and animals, and is retrogradely axonally transported in the rat central nervous system, being an effective suicide transport agent. Here we studied the binding, endocytosis, intracellular routeing, degradation and exocytosis of this RIP. The interaction of volkensin with HeLa cells was compared to that of nigrin b, as an example of a type 2 RIP with low toxicity, and of ricin, as a reference toxin. Nigrin b and volkensin bound to cells with comparable affinity (approx. 10(-10) M) and had a similar number of binding sites (2 x 10(5)/cell), two-log lower than that reported for ricin. The cellular uptake of volkensin was lower than that reported for nigrin b and ricin. Confocal microscopy showed the rapid localization of volkensin in the Golgi stacks with a perinuclear localization similar to that of ricin, while nigrin b was distributed between cytoplasmic dots and the Golgi compartment. Consistently, brefeldin A, which disrupts the Golgi apparatus, protected cells from the inhibition of protein synthesis by volkensin or ricin, whereas it was ineffective in the case of nigrin b. Of the cell-released RIPs, 57% of volkensin and only 5% of ricin were active, whilst exocytosed nigrin b was totally inactive. Despite the low binding to, and uptake by, cells, the high cytotoxicity of volkensin may depend on (i) routeing to the Golgi apparatus, (ii) the low level of degradation, (iii) rapid recycling and (iv) the high percentage of active toxin remaining after exocytosis.

show abstract

“…Taken together, the data on enzymic activity and on amino‐acid sequence, support the idea that they are actually different type 2 RIPs. During revision of this article, Battelli et al Reported that SNLRP inhibits protein synthesis by a cell‐free system and, at much higher concentration, by cells [30].…”

Section: Resultsmentioning

confidence: 99%

Isolation and partial characterization of a novel and uncommon two‐chain 64‐kDa ribosome‐inactivating protein from the bark of elder (Sambucus nigra L.)

Benito¹,

Citores²,

Iglesias³

et al. 1997

FEBS Letters

View full text Add to dashboard Cite

Ribosome‐inactivating lectins with polynucleotide:adenosine glycosidase activity

Cited by 36 publications

References 31 publications

Analysis of the in planta antiviral activity of elderberry ribosome‐inactivating proteins

Analysis of the in planta antiviral activity of elderberry ribosome‐inactivating proteins

Interaction of volkensin with HeLa cells: binding, uptake, intracellular localization, degradation and exocytosis

Isolation and partial characterization of a novel and uncommon two‐chain 64‐kDa ribosome‐inactivating protein from the bark of elder (Sambucus nigra L.)

Contact Info

Product

Resources

About