Seed Development and Protein Accumulation Patterns in Faba Bean (Vicia faba, L.)

A major objective in faba bean breeding is to improve
its protein
quality by selecting cultivars with enhanced desirable physicochemical
properties. However, the protein composition of the mature seed is
determined by a series of biological processes occurring during seed
growth. Thus, any attempt to explain the final seed composition must
consider the dynamics of the seed proteome during seed development.
Here, we investigated the proteomic profile of developing faba bean
seeds across 12 growth stages from 20 days after pollination (DAP)
to full maturity. We analyzed trypsin-digested total protein extracts
from the seeds at different growth stages by liquid chromatography-tandem
mass spectrometry (LC-MS/MS), identifying 1217 proteins. The functional
clusters of these proteins showed that, in early growth stages, proteins
related to cell growth, division, and metabolism were most abundant
compared to seed storage proteins that began to accumulate from 45
DAP. Moreover, label-free quantification of the relative abundance
of seed proteins, including important globulin proteins, revealed
several distinct temporal accumulation trends among the protein classes.
These results suggest that these proteins are regulated differently
and require further understanding of the impact of the different environmental
stresses occurring at different grain filling stages on the expression
and accumulation of these seed storage proteins.

在豌豆育种领域，一个重要的目标是通过筛选具有增强的优良物理化学特性的品种，从而提升其蛋白质质量。然而，成熟种子的蛋白质组成是由种子生长过程中一系列生物过程所决定的。因此，对最终种子组成的解释必须考虑种子蛋白质组在种子发育过程中的动态变化。本研究中，我们调查了从授粉后20天（DAP）至完全成熟期，豌豆种子在12个生长阶段的蛋白质组学特征。通过对不同生长阶段种子中经胰蛋白酶消化的总蛋白提取物进行液相色谱-串联质谱（LC-MS/MS）分析，我们鉴定出了1217种蛋白质。这些蛋白质的功能簇显示，在早期生长阶段，与细胞生长、分裂和代谢相关的蛋白质相较于开始从45 DAP积累的种子储藏蛋白更为丰富。此外，通过对包括重要球蛋白在内的种子蛋白相对丰度的无标记定量分析，揭示了蛋白质类别间不同的时间积累趋势。这些结果提示，这些蛋白质的调控机制存在差异，并需要进一步探究不同环境胁迫对种子储藏蛋白表达和积累的影响。