Characterizing Regulatory and Functional Differentiation between Maize Mesophyll and Bundle Sheath Cells by Transcriptomic Analysis

• Published in: Plant physiology (Bethesda) Vol. 160; no. 1; pp. 165 - 177
• Main Authors: Chang, Yao-Ming, Liu, Wen-Yu, Shih, Arthur Chun-Chieh, Shen, Meng-Ni, Lu, Chen-Hua, Lu, Mei-Yeh Jade, Yang, Hui-Wen, Wang, Tzi-Yuan, Chen, Sean C.-C., Chen, Stella Maris, Li, Wen-Hsiung, Ku, Maurice S.B.
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Biologists 01.09.2012
• Subjects: Biological and medical sciences; bundle sheath cells; C4 plants; carbon; Cell Differentiation; cell division; Cell Wall - genetics; Cell Wall - metabolism; Cell walls; Cells; Chloroplasts; Chromosome Mapping; Corn; data collection; Fundamental and applied biological sciences. Psychology; gene expression; Gene Expression Profiling; Gene Expression Regulation, Plant; Genes; Genes, Plant; Genome Analysis; hydrogen; leaves; mesophyll; Mesophyll Cells - cytology; Mesophyll Cells - metabolism; metabolites; oxygen; Photosynthesis; Plant cells; Plant Cells - metabolism; Plant Epidermis - genetics; Plant Epidermis - metabolism; Plant Leaves - cytology; Plant Leaves - genetics; Plant Leaves - metabolism; Plant physiology and development; Plant Proteins - metabolism; Plant Vascular Bundle - cytology; Plant Vascular Bundle - genetics; Plant Vascular Bundle - metabolism; Plants; Plasmodesmata - genetics; Plasmodesmata - metabolism; post-translational modification; Protein Biosynthesis; protein degradation; Protein Transport; Protoplasts - cytology; Protoplasts - metabolism; RNA; RNA, Plant - analysis; RNA, Plant - genetics; sequence analysis; Signal Transduction; transcription (genetics); transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; Transcriptome; Transcriptomes; transcriptomics; transporters; Zea mays; Zea mays - cytology; Zea mays - genetics; Zea mays - metabolism; Monocotyledones; Zea mays; Mesophyll; Plant physiology; Gramineae; Vascular bundle; Angiospermae; Transcriptome; Spermatophyta; Plant leaf; Cereal crop
• ISSN: 0032-0889; 1532-2548; 1532-2548
• DOI: 10.1104/pp.112.203810

To study the regulatory and functional differentiation between the mesophyll (M) and bundle sheath (BS) cells of maize (Zea mays), we isolated large quantities of highly homogeneous M and BS cells from newly matured second leaves for transcriptome profiling by RNA sequencing. A total of 52,421 annotated genes with at least one read were found in the two transcriptomes. Defining a gene with more than one read per kilobase per million mapped reads as expressed, we identified 18,482 expressed genes; 14,972 were expressed in M cells, including 53 M-enriched transcription factor (TF) genes, whereas 17,269 were expressed in BS cells, including 214 BS-enriched TF genes. Interestingly, many TF gene families show a conspicuous BS preference in expression. Pathway analyses reveal differentiation between the two cell types in various functional categories, with the M cells playing more important roles in light reaction, protein synthesis and folding, tetrapyrrole synthesis, and RNA binding, while the BS cells specialize in transport, signaling, protein degradation and posttranslational modification, major carbon, hydrogen, and oxygen metabolism, cell division and organization, and development. Genes coding for several transporters involved in the shuttle of C 4 metabolites and BS cell wall development have been identified, to our knowledge, for the first time. This comprehensive data set will be useful for studying M/BS differentiation in regulation and function.