Modulation of Bax Inhibitor-1 and cytosolic Ca2+ by cytokinins in Nicotiana tabacum cells.

The protein Bax Inhibitor-1 (BI-1) has recently emerged as a negative regulator of plant programmed cell death (PCD), but how it functions at the biochemical level remains unknown. To elucidate its regulation and mode of action, we used suspension cells of Nicotiana tabacum to study the effects of cytokinins (CKs) on the expression level of NtBI-1 via western analysis. We found that the NtBI-1 protein is up-regulated following treatments with CKs at concentrations inducing a stress response (determined by growth reduction and PR1a accumulation), but not at PCD-inducing concentrations.

Evaluation of the roles of apoptosis, autophagy, and mitophagy in the loss of plating efficiency induced by Bax expression in yeast.

We found recently that, in yeast cells, the heterologous expression of Bax induces a loss of plating efficiency different from that induced by acute stress because it is associated with the maintenance of plasma membrane integrity (Camougrand, N., Grelaud-Coq, A., Marza, E.

Molecular characterization of two plant BI-1 homologues which suppress Bax-induced apoptosis in human 293 cells.

To date, few homologues of animal programmed cell death (PCD) regulators have been identified in plants. Among these is the plant Bax Inhibitor-1 (BI-1) protein, which possesses, like its human counterpart, the ability to suppress Bax-induced lethality in yeast cells. As the role of BI-1 in the regulation of plant PCD remains to be elucidated, we cloned BnBI-1 and NtBI-1 from cDNA libraries of oilseed rape ( Brassica napus L.

Antisense down regulation of NtBI-1 in tobacco BY-2 cells induces accelerated cell death upon carbon starvation.

Bax inhibitor-1 (BI-1) protein is proposed to be a conserved programmed cell death suppressor. In this report, we investigate the anti-apoptotic function of plant BI-1 by antisense (AS) down regulation of NtBI-1 in Nicotiana tabacum cv. BY-2 cells.