Expression of Plant Genes for Arbuscular Mycorrhiza-Inducible Phosphate Transporters and Fungal Vesicle Formation in Sorghum, Barley, and Wheat Roots

Abstract

Sorghum shows strong growth stimulation on arbuscular mycorrhizal (AM) symbiosis, while barley and wheat show growth depression. We identified the AM-inducible phosphate transporter genes of these cereals. Their protein products play major roles in phosphate absorption from arbuscules, intracellular fungal structures. Unexpectedly, barley and wheat expressed the AM-inducible genes at high levels. Hence the cause of their growth depression appears to be unrelated to the transcription of these genes. Notably, fungal vesicles were formed significantly more in barley and wheat than in sorghum. This study yielded new clues for investigation of the mechanism underlying these various responses.

Genome-wide Identification, Characterization, and Expression Analysis of PHT1 Phosphate Transporters in Wheat

“…The Gene ID TRIAE_CS42_4BL_TGACv1_320302_AA1034400 matched with TaPHT1.2-4B and TaPHT1.9-4B ; and no Gene ID was found to match with TaPHT1.1-4B and TaPHT1.10-U cloned in the current study or TaPHT1.11-4B (former name TRIae; Pht1;11 ) cloned by Sisaphaithong et al (2012). Therefore, we identified a total of 36 TaPHT1 genes (Supplementary Table S3).…”

“…TaPHT1.5 in Branch IV and TaPHT1.7 in Branch III were expressed at very low levels in both of the hydroponic culture and field experiment ( Figures 3C, 4C ). The reported AM fungi inducible PHT1 s were grouped into Branch VI ( Figure 1 ), including TaPHT1.8 and TaPHT1.11 from wheat, HvPHT1.8 and HvPHT1.11 from barley, ZmPHT1.6 from maize (Glassop et al, 2005; Sisaphaithong et al, 2012), and OsPHT1.11 from rice (Paszkowski et al, 2002). Here, we found that TaPHT1.8 was upregulated by low P treatment in the field experiments ( Figures 4C, 6D ), but not by low P treatment in the hydroponic culture ( Figure 3C ).…”

“…They did not find a clear pattern in the expression of the four HvPHT1.1 paralogs ( HvPHT1.1, 1.2, 1.9, 1.10 ) among the four barley genotypes, but observed that the expression of HvPHT1.3 and 1.6 positively correlated with P utilization efficiency. HvPHT1.8 and HvPHT1.11 (known as HvPT11 ) have been demonstrated to be specifically activated by arbuscular mycorrhizal (AM) fungi (Glassop et al, 2005; Sisaphaithong et al, 2012), indicating their possible roles in the mycorrhizal pathway of Pi uptake.…”

“…Shukla et al (2016) found that aleurone accumulates more Pi with higher expression of TaPHT1 genes compared to endosperm. TaPHT1.8-6A (known as TRIae; Pht1; myc , Glassop et al, 2005, GenBank: AJ830009), TaPHT1.11-4A (known as TRIae; Pht1; 12 , GenBank: AB753271), TaPHT1.11-4B (known as TRIae; Pht1;11 , GenBank: AB753270), and TaPHT1.11-4D (known as TRIae; Pht1; 10 , GenBank: AB753269) have been found to be induced by AM fungi (Glassop et al, 2005; Sisaphaithong et al, 2012). Although expression of some PHT1 genes has displayed correlation with P use-related traits in wheat and its close relative barley under controlled conditions, an on-farm field-scale investigation is required to explore the PHT1 genes contributing to P uptake and utilization, as the response of PHT1 genes to P supply level under controlled conditions greatly differed from that under field conditions.…”

Differential Growth Responses of Rice Cultivars to an Arbuscular Mycorrhizal Fungus, Funneliformis mosseae

“…Rice is also a suitable material for investigating the molecular mechanisms of symbiosis with arbuscular mycorrhizal (AM) fungi, which colonize the roots of most land plant species [5][6][7][8][9]. However, the number of reports describing the growth response of rice plants to AM fungi is unexpectedly much smaller than those of other crops such as maize, sorghum, legumes, and vegetables [10,11]. The reason may be that rice plants are grown mainly in anoxic paddy fields, in which the presence of AM fungi is still a matter of debate [12][13][14][15].…”