Expression of neuronal protein Tau in Candida albicans, strain 36232

College of Staten Island

Nicholas Ferraro

Overview of Candida albicans

• Dimorphic fungal pathogen.

• Budding form and filamentous form which contributes to host tissue invasiveness and fungal

pathogenicity.

• Cells adhere during hyphae formation resulting in biofilm formation which is a polymeric

conglomeration of extracellular proteins and polysaccharides.

• Hyphae formation is mediated by actin and microtubules.

• Actin plays a significant role in elongation of filaments.

• Microtubules function in nuclei positioning in filaments and regulation of hyphael

morphogenesis.

Neuronal protein Tau

• Tau is a hydrophilic phosphoprotein.

• Tau plays a role in microtubule assembly, stabilization and bundling in the neurons of the

mammalian brain.

• Phosphorylation of Tau is developmentally regulated and the level of Tau phosphorylation controls

the normal interactions with microtubules.

• When Tau is in a hyperphosphorylated state, it dissociates from microtubules and self assemblies into

filaments and neurofibrillary tangles, as seen in Alzheimer's disease.

MECHANISM OF ALZHEIMERS

CURRENT RESULTS

Biofilm Assay• In well “A” containg the parental

strain 36232 we can see strong

adherence compared with

36232-CMV and 36232-CMV-

Tau. This is indicating that the

more adherence to the well the

less filamentation occurring.

C. Albicans 36232 C.Albicans 36232-CMV C. Albicans 36232-CMV -Tau

24 hour incubation

36232 36232-CMV 36232CMV-Tau

48 hour incubation

36232 36232-CMV 36232-CMV-Tau

72 hour incubation

36232 36232-CMV 36232-CMV-Tau

96 hour incubation

36232 36232-CMV 36232-CMV-Tau

7 day incubation

36232

36232 CMV

36232 TAU

36232 TAU

36232 – ALEXA 488 36232 – ALEXA 488 with DAPI

Tau 2-ALEXA 488 Tau 2 – ALEXA 488 with DAPI

Tau expression in: 36232, 36232-CMV, and 36232-CMV-Tau

• At 24 hours we see the first signs of filamentation occurring in the CMV derivative. Few filaments are seen in

36232 with non in 36232-CMV-Tau.

• At 48, and 72 hours we begin to see long filaments in every field of 36232-CMV as well as short filaments

with adhesion in 36232-CMV-Tau. There is still few filamentous growth in 36232.

• At 96 hours we see large long filaments with in 36232, and long filaments in 36232-CMV. 36232-CMV-Tau

shows short filaments with adhesion.

• At the 7 day marker, we see similar filamentation in both 36232 and 36232-CMV. In 36232-CMV-Tau we still

see small aggregates of short filaments with much adhesion.

• With regard to the images obtained from the confocal microscopes we can see labeling of tau in the Tau2

strain however, there is labeling also found in the parental strain.

Does Tau effect filamentation?• In the 7 day period we can see morphological differences in filamentation between 36232, 36232-CMV, and

36232-CMV-Tau. We can see by the seventh day of incubation both 36232 and 36232-CMV-Tau look similar in

filamenation length and adhesion. It is 36232-CMV-Tau that has the significant difference of short filaments with

much adhesion.

• With regard to the images obtained by the confocal microscope, we can see that tau does have an effect on

filamentation however, labeling of both the parental strain and the Tau2 strain indicate that there maybe be cross

interaction between the antibody and another site of homology or protocol revision may be in order.

• Unfortunately, results from the 36232-CMV plasmid control were unable to be obtained. Further analysis such as

Western Blot analysis, NMR and TEM is required to further establish the expression of Tau.