F-box was revealed as the worse gene by all three approaches. This is consistent with the genome-wide investigation where these genes are among five the most stable and supports the suggestion that the orthologs of the novel Carbadox reference genes that they have identified could serve the same purposes in other species. Similar results were obtained in the study of gene expression stability in tomato �C one of the few studies adopting new reference genes proposed in. Optimal number of reference genes calculated by geNorm is two�C Expressed1 and CACS. However taking into account that NormFinder does not support high stability of CACS but lists SAND as the most stable and that CACS expression is known to be affected by several treatments we suggest using three reference genes – Expressed1, CACS and SAND. We expect that use of these genes for normalization in the future studies evaluating gene expression in buckwheat using qRT-PCR will improve the sensitivity and reproducibility of the results. In contrast, the choice of non-optimal reference gene can lead to inaccurate results. The processivity of DNA Estradiol Benzoate replication requires a 59R39 replicative helicase DnaB in Escherichia coli – to unwind double stranded DNA in front of, and in interaction with, the replisome. The hexameric DnaB protein forms a stable ring-shaped structure that needs to be opened prior to its placement on a single-stranded DNA. In E. coli, this function is ensured by DnaC, the helicase loader and a ring breaker, which remains stably bound to DnaB until activation of the replicative helicase by the primase. The replicative helicase needs to be loaded onto DNA at two different stages of DNA replication: the initiation of replication and the reactivation of arrested replication forks. At the time of replication initiation, the complex DnaB6DnaC6 is recruited after the formation of the open complex and involves the initiator protein, DnaA, and likely DiaA. Other mechanisms are specified to reload the replicative helicase during RF reactivation. The most prominent pathway involves PriA and the primosomal proteins PriB and DnaT. In this case, the 39R59 helicase activity specified by PriA is required to make available a sufficient length of single-stranded DNA to allow the assembly of the primosomal proteins and the subsequent loading of DnaB onto the lagging strand. Other proteins, such as Rep, which also specifies a 39R59 helicase activity, and PriC may have important functions during the reactivation of arrested RF. dnaC2 is a thermosensitive mutant of the replicative helicase loader described as a slow stop mutant for DNA synthesis : at non-permissive temperature, new rounds of replication cannot initiate while most ongoing rounds of replication continues through to completion. The proportion of dnaC2 cells in which replication is incomplete was estimated to be 18% at a non-permissive temperature of 38uC, which indicates that DnaC activity is not only indispensable for the initiation of replication but is also required during RF reactivation. Yet, the severe and deleterious phenotypes associated with a priA2 null mutant, in which arrested RF cannot be reactivated, appear far more severe than what would be expected if a mere 18% of RF were arrested during DNA replication. This discrepancy suggests that the cells, in which arrested RF were not reactivated, represent only a fraction of those in which RF were inactivated. To establish whether some arrested RF are reactivated in dnaC2 cells at non-permissive temperature, we designed an assay allowing us to compare the accumulation of arrested RF in dnaC2 cells at non-permissive temperature in a priA+ and in a priA2 background.