Phenotypically abnormal cotyledonary Vitis vinifera embryos differ in anatomy, endogenous hormone levels and...

Area of Science:

• Plant Biotechnology
• Developmental Biology
• Genomics

Background:

• Somatic embryogenesis (SE) in perennial fruits like grapevine (Vitis vinifera L.) is complex and can lead to malformed embryos.
• The genetic and hormonal factors influencing SE morphology remain poorly understood.

Purpose of the Study:

• To investigate the causes of morphological variations in grapevine somatic embryos.
• To identify gene networks and molecular players regulating somatic cotyledon development.

Main Methods:

• Comparative analysis of normal (NCEs) and abnormal (ECEs, VCEs, FCEs) grapevine cotyledonary embryos.
• Quantification of endogenous phytohormones (indoleacetic acid and abscisic acid).
• Transcriptome analysis and weighted gene co-expression network analysis (WGCNA).

Main Results:

• Morphological differences correlate with endogenous hormone levels; normal embryos had higher IAA and ABA.
• Significant differences in hormone signaling pathway gene expression were observed between normal and abnormal embryos.
• WGCNA identified gene modules associated with SE, highlighting ERF family genes and transcription factors (TFs).
• Specific protein kinases, small heat shock proteins (sHSPs), and TFs were linked to normal embryo formation.

Conclusions:

• Endogenous hormone levels and specific gene expression patterns, particularly involving ERF TFs, play crucial roles in regulating grapevine somatic embryo morphology.
• These findings offer insights into plant regeneration and provide a basis for functional genomic studies of malformed embryos.