Comparative transcriptomic profiling of Vitis vinifera under high light using a custom-made array and the Affymetrix...

Area of Science:

• Plant Biology
• Molecular Biology
• Stress Physiology

Background:

• Abiotic stress, including excess light, induces oxidative stress in plants via reactive oxygen species accumulation.
• In vitro propagated plants face oxidative stress when transferred to ex vitro conditions under high light.
• Understanding these stress responses is crucial for plant research and agriculture.

Purpose of the Study:

• To investigate if gene pathways activated during grapevine transfer from in vitro to ex vitro conditions mirror those of light stress.
• To compare gene expression profiles using a Vitis vinifera GeneChip (VvGA) and a custom light stress array (LSCA).

Main Methods:

• Utilized Vitis vinifera Affymetrix GeneChip (VvGA) for broad gene expression analysis.
• Employed a custom array of genes responsive to light stress (LSCA) with real-time reverse transcriptase PCR (qRT-PCR) for focused analysis.
• Compared gene expression profiles between the two methods.

Main Results:

• LSCA highlighted 'protein metabolism and modification', 'signaling', and 'anti-oxidative' genes.
• VvGA showed significant variation in 'cell wall metabolism' and 'secondary metabolism' genes.
• LSCA revealed a late but significant response of heat shock genes (Hsp100, Hsp70) involved in protein repair.

Conclusions:

• Gene expression patterns during ex vitro transfer share common attributes with abiotic stress defense pathways.
• The custom qRT-PCR approach (LSCA) is effective for focused gene expression studies, especially for species lacking commercial arrays.
• Heat shock proteins (Hsp100, Hsp70) are critical for managing stress-induced protein damage during plant recovery.