Proteolysis is considered as a crucial factor determining the proper development of the plant and its efficient functioning in variable environmental conditions. The role of proteases in protein quality control and protein turnover processes is well documented. The results of studies performed in recent years reveal; however, that proteolytic enzymes also participate in signal transduction pathways by releasing membrane-anchored transcription factors in the process known as regulated intramembrane proteolysis (RIP). The first described intramembrane protease was identified in human cells in 1997. In turn, the first plant intramembrane protease was identified in 2005, in Arabidopsis thaliana. To date, most studies concerning the RIP process in plants have been performed on this model plant. The knowledge concerning the potential physiological role of RIP is very limited. However, continuously accumulating information concerning this issue indicates that RIP, like the other proteolytic mechanisms, has a significant effect on plant ontogenesis, acclimatization and fertility. The aim of this article is to gather and systemize the present knowledge concerning the intramembrane proteases in A. thaliana.

Unfortunately, two reference citations were published incorrectly in the original publication of the article. In the last section before the Conclusion part, the 2nd and 3rd sentence should read as:Studies performed on spp heterozygotes indicate that the protein is involved in pollen development and germination (Han et al. 2009). The SPPL1, SPPL2 and SPPL3 transcripts were detected in the tissues, roots, rosette leaves, cauline leaves, stems, flower-bud clusters, siliques and dry seeds (Tamura et al. 2008). The significant accumulation of all three transcripts was, however, observed during seed germination.The online version of the original article can be found under