Yeasthypha Dimorphism

Yeast-hypha dimorphism is believed to be hugely important in the virulence of C. albicans (Kumamoto & Vinces, 2005), and has been the focus of a significant amount of research in the past. Transcript profiling studies have built upon the knowledge obtained from previous studies (Nantel et al., 2002; Sohn et al., 2003; Lee et al., 2004; Bachewich et al., 2005; Enjalbert & Whiteway, 2005; Kadosh & Johnson, 2005; Singh et al., 2005; Cao et al., 2006).

Efglp has been confirmed as an important regulator of the yeast-hypha dimorphic switch (Nantel et al., 2002; Sohn et al., 2003; Bachewich et al., 2005; Singh et al., 2005; Cao et al., 2006). During the formation of hyphae in the presence of macrophages genes involved in galactose, protein, and lipid metabolism and stress response genes underwent changes in transcription. The promoters of differentially expressed genes were found to contain binding sites for Cphl and Efgl (Singh et al., 2005). Flo8p was shown to interact with Efgl, and is involved in controlling a subset of Efglp-regulated genes, which mostly show hypha-specific expression

(including HGC1 and IHD1), with the flo8 strain unable to form hyphae (Cao et al., 2006). However, Efglp plays a major role in the induction and repression of cell wall genes in both yeast and hyphae (Sohn et al., 2003). The SIT4 gene has also been demonstrated to be involved in induction of hypha-specific genes, with the expression of two glucanase-encoding genes, XOG1 and YNR67, found to rely entirely upon Sit4p (Lee et al., 2004).

Many of the genes expressed in hyphal cells have been found to be repressed under yeast growth conditions. Repression can occur through the actions of Nrglp and Tuplp (Kadosh & Johnson, 2005) or can involve regulation of histone genes, as found in response to the quorum sensing molecule farnesol (Enjalbert & Whiteway, 2005).

Yeast-hypha dimorphism has also been studied by proteomic analyses (Pitarch et al., 2002; Choi et al., 2003; Ebanks et al., 2006). Studies examining the cell wall proteins of yeast and hyphal forms found that there were a number of proteins upregulated in the hyphal form (Pitarch et al., 2002; Ebanks et al., 2006). Upregulated proteins included Hsp70s and Hsp90, fructose bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, phos-phoglycerate mutase, alcohol dehydrogenase, enolase, pyruvate kinase, agglutinin-like sequence proteins (Als family), and myo-inositol-1-phosphate synthase (Inolp). A further study found proteins Pralp. Phrlp, and Tsalp to be upregulated in hyphal cells compared to yeasts (Choi et al., 2003). However, only transcription of PHR1 was found to be increased, suggesting that the other two proteins are modulated at the post-transcriptional level. Proteomic studies have also identified some yeast-specific proteins (Ebanks et al., 2006).

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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