Computational prediction combined with proteogenomics unveils widespread non-AUG translation initiation events in plants

ABSTRACT: Non-AUG translation initiation is crucial for regulating translation, which can generate N-terminally extended protein isoforms with diverse biological functions. However, a comprehensive view of non-AUG translation initiation events with N-terminal extensions (NTEs) across monocots and dicots remains limited. Here, we identified a total of 879 transcripts undergoing non-AUG translation initiation events with NTEs in maize, rice and soybean using a computational prediction-combined proteogenomic strategy. Over half the non-AUG initiated candidates had multiple putative upstream translation initiation sites (uTISs), with GUG being the most common uTIS, followed by CUG in monocots and AUU in the dicot. Sequence context analyses showed that these putative uTISs tended to have Kozak sequence and high AG content favoring initiation. Additionally, non-AUG initiated candidates had longer 5' untranslated regions (UTRs) across all species, whereas other transcript features showed contrasting trends between monocots and the dicot. Furthermore, non-AUG initiated candidates in maize were implicated in essential cellular processes and diverse functional signals were observed in the NTEs, suggesting their biological implications. This study provides a comprehensive landscape of the shared and distinct characteristics of non-AUG translation initiation between monocot and dicot plants, and highlights the complexity of genetic decoding in shaping the dynamic composition of plant proteomes.

INSTRUMENT(S):

ORGANISM(S): Oryza Sativa (rice) Zea Mays (maize) Glycine Max

TISSUE(S): Plant Cell, Leaf

SUBMITTER: Yuqian Zhang  

LAB HEAD: Liuji Wu

PROVIDER: PXD058528 | Pride | 2026-04-27

REPOSITORIES: Pride