Pleiotropic function of the SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE gene TaSPL14 in wheat plant architecture

Abstract

Main conclusion The function of SQUAMOSA PROMOTER-BINDING PROTEIN-BOX gene TaSPL14 in wheat is similar to that of OsSPL14 in rice in regulating plant height, panicle length, spikelet number, and thousand-grain weight of wheat, but differs during tiller development. TaSPL14 may regulate spike development via ethylene-response gene EIN3-LIKE 1 (TaEIL1), ETHYLENE-RESPONSIVE TRANSCRIPTION FACTOR 2.11 (TaRAP2.11), and ETHYLENE-RESPONSIVE TRANSCRIPTION FACTOR 1 (TaERF1), but not DENSE AND ERECT PANICLE 1 (TaDEP1) in wheat. Abstract The SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE gene OsSPL14 from rice is considered to be a major determinant of ideal plant architecture consisting of few unproductive tillers, more grains per spike, and high resistance of stems to lodging. However, the function of its orthologous gene, TaSPL14, in wheat is unknown. Here, we reported the functional similarities and differences between TaSPL14 and OsSPL14. Similar to OsSPL14 knock-outs in rice, wheat TaSPL14 knock-out plants exhibited decreased plant height, panicle length, spikelet number, and thousand-grain weight. In contrast to OsSPL14, however, TaSPL14 did not affect tiller number. Transcriptome analysis revealed that the expression of genes related to ethylene response was significantly decreased in young spikes of TaSPL14 knock-out lines as compared with wild type. TaSPL14 directly binds to the promoters of the ethylene-response genes TaEIL1, TaRAP2.11, and TaERF1, and promotes their expression, suggesting that TaSPL14 might regulate wheat spike development via the ethylene-response pathway. The elucidation of TaSPL14 will contribute to understanding of the molecular mechanisms that underlie wheat plant architecture.

The CRISPR/Cas9-Mediated Modulation of SQUAMOSA PROMOTER-BINDING PROTEIN-LIKE 8 in Alfalfa Leads to Distinct Phenotypic Outcomes

“…Many SPL genes are targeted by microRNA156 (miR156), which is an abundant and highly conserved miRNA in plants that regulates the expression of its target genes through transcript cleavage and translational inhibition ( Gandikota et al, 2007 ; Gao et al, 2016 ). While this group of transcription factors tends to be well-conserved across monocot and eudicot plant species ( Wang et al, 2009 ), family members may have distinct functions between species in certain cases ( Preston et al, 2016 ; Gou et al, 2019 ; Cao et al, 2021 ).…”

ccnWheat: A Database for Comparing Co-expression Networks Analysis of Allohexaploid Wheat and Its Progenitors

“…GO analysis of the WAPO1 co-expression network in AABBDD showed that these genes were related to reproductive shoot system development and post-embryonic development (Figure S6A). GSEA results for the network (Figure S6B) also indicated that the network of WAPO1 corresponded to floral transition, in that some gene sets were significantly enriched with reproductive meristem phase change, miR156 miRNA_target_network (miR156 could regulate TaSPL14 and TaSPL17 [60,64]), and SBP TF. After exploring the regulatory regions through motif analysis, we found a novel motif of CArG (CCWWWWWWGG) specifically identified in the promoter region of the WAPO-A1 gene in AABBDD but not in AABB.…”

“…There are three genes (TraesCS7A02G481600 (WAPO-A1), TraesCS7B02G384000 (WAPO-B1), TraesCS7D02G468700 (WAPO-D1)) in AABBDD; two genes (TRIDC7AG067090 (not expressed), TRIDC7BG060970) in AABB; no gene in AA and one gene (evm.TU.Contig391.11) in DD. We searched the co-expression network of WAPO1 using ccnWheat (Figure 4), and found that spike development related gene wheat FLO/LFY WFL [59], TaSPL14 [60], TaSPL17 [61],…”

Genome-wide investigation of SQUAMOSA promoter binding protein-like transcription factor family in pearl millet (Pennisetum glaucum (L) R. Br.)

“…Some of the 14 SBP genes in papaya (Carica papaya) are induced at a specific stage in fruit ripening and this process can be controlled by the phytohormone ethylene (Xu et al, 2020). TaSPL14, a close OsSPL14 homolog in wheat (Triticum aestivum), does not regulate the tiller number but binds to the promoters of the ethylene-related genes TaEIL1, TaRAP2.11, and TaERF1 and increases their expression, thereby regulating plant height, panicle length, the spikelet number, and grain weight (Cao et al, 2021). In this study, ABA-responsive elements and stress-responsive elements were found in most of the PgSBP promoters and ABA treatments reduced the expression levels of these genes.…”