Revision as of 02:29, 28 October 2020

clb2 promoter (during G2 phase)

Purpose

Works for B-type cyclin, the cell synchronization device involved in cell cycle progression, activates CDC28p to promote the yeast cell transition from G2 to M phase;

Principle

It is a promoter that promotes transcription in G2 of the yeast cell cycle. If you want to express your proteins in G2 of the yeast cell cycle, you can add the CLN2 sequence before your gene sequence, then put them in a yeast plasmid. After transformation into bacteria, you can get the protein you want from the metabolic product of the strain.
Sequence and Features

BNU-China 2020 - Contribution

We summarized information about CLB2 promoter from four articles and documented the function of this promoter. It was verified in the study that CLB2 promoter can periodically regulate the transcription of foreign proteins, and it is proved that the UAS is responsible for regulating.

Research done by Trcek, Tatjana replaced the coding sequence of CLB2 with DOA1 in yeast. The level of DOA1 mRNA expressed from the CLB2 promoter as cell divided is shown in Figure 1. It strongly proved that CLB2 promoter promotes transcription in G2 of the yeast cell cycle.

Figure 1. DOA1 mRNA expressed from the CLB2 promoter and the integration cassette used. Colors denote gene origins: ACT1, blue; DOA1 pale blue; CLB2 violet.The transcription effect of CLB2 promoter varies with different stages of the cell cycle(Trcek, Tatjana. et al, 2011)

In another research done by Maher M, they sequenced the CLB2 promoter region and defined important features of the CLB2 promoter (Figure 2). They also defined upstream activation sequence (UAS) lies within the -362 to -131 region. UAS is essential for cell cycle regulation. By experiment, they verified the function of this region (Figure 3).

So, it is necessary to contain this region when periodic function of CLB2 promoter is required.

Figure 2. Sequence and features of the CLB2 promoter. The major start site at 11 is indicated by an arrow. The ATG translation initiator codon is at position 362. Putative TATA boxes is at positions -19 and -113 (underlined). Four sequences which represent possible Mcm1 binding sites is in boldface type and underlined.

Figure 3. Ability of UAS deletions to support cell cycle-regulated transcription. UAS sequences mapped by deletion analysis as for panel A were inserted upstream of a ubiYlacZ reporter gene. Cells were synchronized with a-factor, and ubiYlacZ, CLB2, H2A, and Prt1 transcript levels were assessed by Northern analysis in a synchronous population of cells.

Reference

[1]Trcek, Tatjana et al. “Single-molecule mRNA decay measurements reveal promoter- regulated mRNA stability in yeast.” Cell vol. 147,7 (2011): 1484-97.

[2]Maher M, Cong F, Kindelberger D, Nasmyth K, Dalton S. Cell cycle-regulated transcription of the CLB2 gene is dependent on Mcm1 and a ternary complex factor. Mol Cell Biol. 1995;15(6):3129-3137.

[3]Hood JK, Hwang WW, Silver PA. The Saccharomyces cerevisiae cyclin Clb2p is targeted to multiple subcellular locations by cis- and trans-acting determinants. J Cell Sci. 2001 Feb;114(Pt 3):589-97.

[4]Kuczera T, Bayram Ö, Sari F, Braus GH, Irniger S. Dissection of mitotic functions of the yeast cyclin Clb2. Cell Cycle. 2010 Jul 1;9(13):2611-9.

[5]Veis, J., Klug, H., Koranda, M., & Ammerer, G. (2007). Activation of the G2/M-specific gene CLB2 requires multiple cell cycle signals. Molecular and cellular biology, 27(23), 8364–8373.