Vascular system
From Purdue Genomics Database Facility
Vascular system
M. Kubo, and T. Nishiyama
(ku-bo@nibb.ac.jp) (tomoakin@kenroku.kanazawa-u.ac.jp)
The vascular system plays a pivotal role in supporting the body and in the transport of water, nutrients, and signals in vascular plants. Although vascular system which is comprised of xylem and phloem tissues (Esau, 1977) is not found in bryophyte, mosses have vascular-like tissues, conducting bundles consisted of water-conducting cells and phloem-like cells with ontogenetic and morphological similarities (Kenrick and Crane, 1997a). However, a large difference in ultrastructure has been reported(Ligrone et al., 2000). Putative orthologues of the A. thaliana genes involved in vascular bundle formation (Sieburth and Deyholos, 2006; Demura and Fukuda, 2007) were identified in S. moellendorffii and P. patens, in concordance with this hypothesis. They include ARF5/MP and IAA12/BDL for auxin signalling, CRE1/WOL/AHK4 and AHP6 for cytokinin signalling, VAN3 for vesicle transport, CVP2 involved in sterol metabolism, KAN, HD-Zip III, VND, NST genes encoding transcription factors, and COV1 encoding unknown protein. Most genes were independently expanded in each lineage, and this expansion is likely related to the evolution of the vascular system; thus, these genes may account for the observed structural differences.
Lignin is a polyphenolic polymer coupled with monolignol, and its deposition on the inner surface of tracheid cell walls is a synapomorphic character of extant vascular plants(Kenrick and Crane, 1997b). Whilst lignin has not been found in extant bryophytes, lignans, oligomers of monolignols, have been reported(Umezawa, 2003). Putative orthologues of all monolignol biosynthetic genes were found in P. patens except FAH1, and these enzymes may be used in the formation of lignans in P. patens.
References
Demura, T., and Fukuda, H. (2007). Transcriptional regulation in wood formation. Trends Plant Sci. 12, 64-70.
Esau, K. (1977). Anatomy of seed plants. (New York: John Wiley & Sons, Inc.). Kenrick, P., and Crane, P.R. (1997a). The Origin and Early Diversification of Land Plants: A Cladistic Study. (Washington, DC: Smithsonian Institution Press). Kenrick, P., and Crane, P.R. (1997b). The origin and early evolution of plants on land. Nature 389, 33-39.
Ligrone, R., Duckett, J.G., and Renzaglia, K.S. (2000). Conducting tissues and phyletic relationships of bryophytes. Phil. Trans. R. Soc. Lond. B 355, 795-813.
Sieburth, L.E., and Deyholos, M.K. (2006). Vascular development: the long and winding road. Curr. Opin. Plant Biol. 9, 48-54.
Umezawa, T. (2003). Diversity in lignan biosynthesis. Phytochem. Rev. 2, 371-390.
Table of gene numbers
| Gene functions | Gene | Gene used as a query | The number of putative orthologs | |||
|---|---|---|---|---|---|---|
| Arabidopsis thaliana | Oryza sativa | Selaginalla moellendorffii | Physcomitrella patens | |||
| Vascular system | VAN3 | VAN3 | 2 | 1 | 1 (2) | 3 |
| Vascular system | DRP1A | DRP1A | 2 | 2 | 0 | 0 |
| Vascular system | CVP2 | CVP2 | 7 | 11 | 2 (4) | 6 |
| Vascular system | VND1 to 7 and NST1 and 2 | VND7 | 13 | 10 | 4 (7) | 8 |
| Vascular system | COV1 2) | COV1 | 4 | 5 | 1 (2) | 4 |
| Lignin biosynthesis | PAL | PAL1 | 4 | 10 | 2 (3) | 11 |
| Lignin biosynthesis | C4H | C4H | 1 | 2 | 1 (2) | 6 |
| Lignin biosynthesis | 4CL1 2) | 4CL1 | 4 | 5 | 2 (3) | 4 |
| Lignin biosynthesis | HCT 7) | HCT | 2 | 2 | 1 (2) | 1 |
| Lignin biosynthesis | C3H | C3H | 1 | 2 | 1 (2) | 1 |
| Lignin biosynthesis | CCOAOMT1 2) | CCOAOMT1 | 1 | 1 | 3 (6) | 1 |
| Lignin biosynthesis | CCR1 and 2 | CCR2 | 2 | 13 | 3 (5) | 1 |
| Lignin biosynthesis | CAD1 to 9 | CAD9 | 9 | 8 | 5 (7) | 2 |
| Lignin biosynthesis | FAH1 1) | FAH1 | 2 | 2 | 0 | 0 |
| Lignin biosynthesis | COMT 2) | COMT | 13 | 11 | 16 (28) | 3 |
Table of gene models in the assembly
| protein id | gene name | annotated by |
| 451405 | VAN3-1 | |
| 451407 | VAN3-2 | |
| 111750 | IP5P1-1 | |
| 136207 | IP5P1-2 | |
| 97137 | IP5P2-1 | |
| 119685 | IP5P2-2 | |
| 140972 | IP5P3-1 | |
| 451408 | IP5P3-2 | |
| 91806 | IP5P4-1 | |
| 171623 | IP5P4-2 | |
| 100973 | VND1-1 | Minoru Kubo |
| 71405 | VND1-2 | Minoru Kubo |
| 402243 | VND2-1 | Minoru Kubo |
| 408624 | VND2-2 | Minoru Kubo |
| 175992 | VND3-1 | Minoru Kubo |
| 57388 | VND3-2 | |
| 93824 | VND4-1 | Minoru Kubo |
| 89986 | VND4-2 | Minoru Kubo |
| 437885 | COV1-1 | Minoru Kubo |
| 171907 | COV1-2 | Minoru Kubo |
| Phenylalanine ammonia lyase | ||
| 450474 | PAL1-1 | Nicholas Bonawitz |
| 450478 | PAL1-2 | Nicholas Bonawitz |
| 271191 | CCoAMT1-1 | |
| 158563 | CCoAMT1-2 | |
| 266699 | CCoAMT2-1 | |
| 101771 | CCoAMT2-2 | |
| 405144 | CCoAMT3-1 |
