Functions of two Malus hupehensis (Pamp.) Rehd. YTPs (MhYTP1 and MhYTP2) in biotic- and abiotic-stress responses

Genome-wide Identification and Expression Analysis of the YTH Domain-containing RNA-binding Protein Family in Citrus Sinensis

“…In apple, expression of MhYTP1 and MhYTP2 is induced during natural leaf senescence; compared with wild-type plants, the leaves of overexpression plants showed earlier yellowing and significantly lower chlorophyll concentrations in A. thaliana and apple. MhYTP2 can interact with acireductone dioxygenase 4 [an ethylene (ET) biosynthesis-related protein] to promote the progress of maturity (Wang et al, 2017a). The fruits of both MhYTP1 and MhYTP2 transgenic tomato plants turned yellow earlier than did those of wild-type plants, indicating that these two YTH domain-containing genes can promote fruit ripening in tomato (Wang et al, 2017c).…”

“…In contrast, the abiotic stress also can affect the expression of YTHs. Several stress-related cis-elements, such as heat stress-responsive elements, droughtresponsive elements, defense-and stress-responsive elements (TC-rich repeats), anaerobic induction elements, and low temperature-responsive elements, all of which respond to external environmental stresses, have been found in the upstream regions of the promoters of YTH members (Li et al, 2014;Wang et al, 2017a), and the MhYTP family was sensitive to chilling and H 2 O 2 conditions and responsive to heat, water deficit, and salt treatment (Wang et al, 2014). Several AtYTH and OsYTH genes presented altered expression in response to abiotic stress.…”

“…However, in overexpressing plants MhYTH1 and MhYTH2, the expression of both of these genes was induced by treatment with SA and MeJA. Furthermore, transgenic plants showed more sensitivity to Diplocarpon mali infection, and expression of the JA signalingrelated genes PLD and COI1, the SA signaling-related genes PR1 and PR5, and the ET-responsive gene ERF3 in transgenic plants was altered, suggesting that MhYTH1 and MhYTH2 are involved in SA and MeJA/ET signaling (Wang et al, 2017a). The present results also showed that the expression of three CitYTH genes (CitYTH1, CitYTH2, and CitYTH10) was significantly altered in response to JA and SA.…”

“…However, direct evidence is limited. Wang et al (2017a) reported that overexpressing MhYTP1 or MhYTP2 in Malus hupehensis led to sensitivity to heat stress, high salinity, and Diplocarpon mali infection, but increased resistance to water logging, chilling stress, drought stress, and nutrition deficiency conditions. However, no biological functions of YTH domain-containing proteins have been reported in other plant species.…”

Genetic Diversity and Heritability of In Vitro Leaf Regeneration Ability in Malus Species

“…By using leaflets from in vitro shoots as explants, transgenic lines have been successfully obtained in many apple cultivars or rootstocks (Bacha et al, 2012;Holefors et al, 2000;Requesens et al, 2014). GL-3, a progeny from open-pollinated Royal Gala with high regeneration capacity, has been used often in recent years for apple transformation using leaves from in vitro shoots (Dai et al, 2013;Wang et al, 2017). Another important reason for using leaves from in vitro shoots as source of explants for regeneration is the excellent uniformity between individuals and the reproducibility between experiments (Bulley and James, 2004).…”