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Summary: Alternative splicing of pre‐mRNAs is crucial for plant growth and development. Serine/arginine‐rich (SR) proteins are a conserved family of RNA‐binding proteins that are critical for both constitutive and alternative splicing. However, how phosphorylation of SR proteins regulates gene transcription and alternative splicing during plant development is poorly understood.We found that the Arabidopsis thaliana L. SR protein‐specific kinase II family proteins (SRPKIIs) play an important role in plant development, including flowering. SRPKIIs regulate the phosphorylation status of a subset of specific SR proteins, including SR45 and SC35, which subsequently mediates their subcellular localization.A phospho‐dead SR45 mutant inhibits the assembly of the apoptosis‐and splicing‐associated protein complex and thereby upregulates the expression of FLOWERING LOCUS C (FLC) via epigenetic modification. The splicing efficiency of FLC introns was significantly increased in the shoot apex of the srpkii mutant. Transcriptomic analysis revealed that SRPKIIs regulate the alternative splicing of c. 400 genes, which largely overlap with those regulated by SR45 and SC35‐SCL family proteins.In summary, we found that Arabidopsis SRPKIIs specifically affect the phosphorylation status of a subset SR proteins and regulate the expression and alternative splicing of FLC to control flowering time. [ABSTRACT FROM AUTHOR]

It is believed that transferring the C4 engine into C3 crops will greatly increase the yields of major C3 crops. Many efforts have been made since the 1960s, but relatively little success has been achieved because C4plant traits, referred to collectively as C4 syndrome, are very complex, and little is known about the genetic mechanisms involved. Unfortunately, there exists no ideal genetic model system to study C4 syndrome. It was previously reported that the Haloxylon species have different photosynthetic pathways in different photosynthetic organs, cotyledons and assimilating shoots. Here, we took advantage of the developmental switch from the C3 to the C4 pathway to study the genetic mechanisms behind this natural transition. We compared the transcriptomes of cotyledons and assimilating shoots using mRNA-Seq to gain insight into the molecular and cellular events associated with C4 syndrome. A total of 2959 differentially expressed genes [FDR≤0.001 and abs (|log2(Fold change)|≥1)] were identified, revealing that the transcriptomes of cotyledons and assimilating shoots are considerably different. We further identified a set of putative regulators of C4 syndrome. This study expands our understanding of the development of C4 syndrome and provides a new model system for future studies on the C3-to- C4 switch mechanism. [ABSTRACT FROM AUTHOR]

Soybean [Glycine max (L.) Merrill] is an important crop worldwide. In this study, a Chinese local soybean cultivar, Hedou 12, was resequenced by next generation sequencing technology to develop INsertion/DELetion (INDEL) markers for genetic mapping. 49,276 INDEL polymorphisms and 242,059 single nucleotide polymorphisms were detected between Hedou 12 and the Williams 82 reference sequence. Of these, 243 candidate INDEL markers ranging from 5-50 bp in length were chosen for validation, and 165 (68%) of them revealed polymorphisms between Hedou 12 and Williams 82. The validated INDEL markers were also tested in 12 other soybean cultivars. The number of polymorphisms in the pairwise comparisons of 14 soybean cultivars varied from 27 to 165. To test the utility of these INDEL markers, they were used to perform genetic mapping of a crinkly leaf mutant, and the CRINKLY LEAF locus was successfully mapped to a 360 kb region on chromosome 7. This research shows that high-throughput sequencing technologies can facilitate the development of genome-wide molecular markers for genetic mapping in soybean., (Copyright © 2015 Song et al.)