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Cis-acting elements play a vital role in regulation of transcription initiation. Several cis-acting elements have been identified in filamentous fungi; however, the fundamental requirements for basic promoter function in basidiomycetes are obscure. In this study, core elements in β1-tubulin promoters of basidiomycetes were functionally characterized. Using transient transformation in Ceriporiopsis subvermispora as a promoter assay, we found that a 14-bp region (β1-tubulin core promoter element, BCE), as well as CT-rich stretch, in the β1-tubulin promoter of the species played a critical role in the expression of a recombinant hph as a reporter gene. In addition, in silico analysis revealed other members of basidiomycetes also harboured the BCE motif as well as CT-rich stretch in the β1-tubulin promoter region, suggesting their functional conservation among the species of basidiomycetes. To confirm the function of BCE, we investigated the effects of BCE motif deletion in the Pleurotus ostreatus β1-tubulin promoter on expression levels of a recombinant luminous shrimp luciferase reporter gene, which was targeted into the Pofcy1 locus. Intriguingly, luciferase activity was abolished when the BCE motif was deleted in the β1-tubulin promoter, strongly demonstrating its essential function in transcription from this promoter on the chromosome. This study clearly demonstrates the crucial role of the BCE as well as the CT-rich stretch regions in the β1-tubulin promoter among basidiomycetes and provides new insights into the fundamental mechanism of transcription initiation in this group.

The original publication of this paper unfortunately contained three errors in Figs. 2B and 3. In Fig. 2B, the TSS site must be counted as "+ 1" instead of "- 1". And we indicated wrong sequences in Fig. 3: the construct "Control" has a missing one "A" in the BCE sequence, and the reverse direction of BCE sequence in the construct "BCEr" must be "GCGGAGTTTCAATT", not "CGCCTCAAGTTAA". For the reasons stated herein, the authors wish to notify the readers that Figs. 2B and 3 must be interpreted as the followings.

Cis-acting elements play a vital role in regulation of transcription initiation. Several cis-acting elements have been identified in filamentous fungi; however, the fundamental requirements for basic promoter function in basidiomycetes are obscure. In this study, core elements in β

The original publication of this paper unfortunately contained three errors in Figs. 2B and 3. In Fig. 2B, the TSS site must be counted as “+ 1” instead of “− 1”. And we indicated wrong sequences in Fig. 3: the construct “Control” has a missing one “A” in the BCE sequence, and the reverse direction of BCE sequence in the construct “BCEr” must be “GCGGAGTTTCAATT”, not “CGCCTCAAGTTAA”. For the reasons stated herein, the authors wish to notify the readers that Figs. 2B and 3 must be interpreted as the followings

The first asymmetric total synthesis of (-)-hippodamine has been accomplished via the concise construction of its azaphenalene core, which is featured by the 2,4,6-chiral piperidine synthesis based on one-pot asymmetric azaelectrocyclization in the partially activated substituent system and the subsequent intramolecular Mannich reaction.

The thermal 6-endo cyclization of N-sulfonyl-2,4-dienamide compounds to produce 4,6-disubstituted 2-piperidinone is described. The observed remarkable substituent effect due to the N-sulfonyl and C3 ethoxycarbonyl groups for acceleration of this 6-endo cyclization strongly suggests that the reaction would proceed via the 6π-azaelectrocyclization of the intermediary imidic acid. On the contrary, the corresponding 5-formyl and 5-acetyl derivatives rapidly cyclized at room temperature to produce the 5-exo cyclized products.

An efficient one-pot synthetic procedure for the synthesis of 2,4-disubstituted pyridines has been successfully established. The method proceeds through a 6pi-azaelectrocyclization-aromatization sequence. Using this method, a wide variety of pyridine structures substituted at the 2-position have been rapidly constructed from vinyl stannanes, vinyl iodide, sulfonamide, and a palladium catalyst. The method was further applied to the solid-phase synthesis wherein the use of a "traceless" sulfonamide linker enabled the rapid preparation of a small library of pyridines with high purity, without any chromatographic separation.

In 3-ethoxycarbonyl-2,4-dienal compounds, a thermal [1,5]-H shift of aldehyde hydrogen easily proceeded to produce the corresponding vinyl ketenes due to the remarkable substituent effect caused by the C3 ester group. The produced ketenes were captured by an alcohol and olefins to afford the corresponding esters and four-membered ring compounds, respectively.

The first asymmetric total synthesis of an indole alkaloid, (−)-20-epiuleine, containing the 2,3,4-trisubstituted piperidine core, was achieved using a stereocontrolled one-pot asymmetric 6π-azaelectrocyclization followed by a stereoselective 1,4-addition reaction of the unsaturated ester with a Grignard reagent resulting from the novel neighboring participation of the hydroxyl group in cis-aminoindanol as a chiral nitrogen source.