Table 2. A list of putative TCS components found in the transcriptome of differentiating barley endosperm transfer cells (ETCs) by 454 sequencing.
| Signalling components | Gene Symbol | Contig ID | Domains$ | Family | Length | Similarity to Rice (%)# |
| Histidine kinases | HvERS1 | 13113, 14069, | GAF, HK | Ethylene receptor | 635 aa§ | 90 |
| HvERS2 | 17016, 19283 | GAF, HK | Ethylene receptor | 630 aa§ | 87 | |
| HvERS3 | 29901 | GAF, HK | Ethylene receptor | 637 aa§ | 88 | |
| HvETR1 | c_321 | HK (H-Q), REC | Ethylene receptor | 796 aa§ | 79 | |
| HvETR2 | 41784 | GAF, HK, REC | Ethylene receptor | 781 aa§ | 81 | |
| HvERS/ETR | 9443, 24802 | GAF | Ethylene receptor | 357 aa | 85 | |
| * , **HvHK1 | 1313 | HK, REC | HK | 1088 aa§ | 52 | |
| * , **HvHK2 | 27729 | HK, REC | HK | 948 aa§ | 78 | |
| HvHK3 | 6273 | HK | HK | 540 aa | 50 | |
| **HvHK4 | 27825 | CHASE, HK, REC | Cytokinin receptor | 986 aa§ | 84 | |
| HvHK5 | 12351 | CHASE, HK, REC | Cytokinin receptor | 1019 aa§ | 77 | |
| HPt elements | HvHP1 | c_2558 | HPt | HPt | 148 aa§ | 60 |
| **HvHP2 | 20816 | HPt | HPt | 143 aa§ | 60 | |
| HvHP3 | 19623 | HPt | HPt | 141 aa§ | 82 | |
| HvPHP1 | 8606 | HPt (H-R) | Pseudo-HPt | 130 aa | 52 | |
| HvPHP2 | 10701 | HPt (H-Q) | Pseudo-HPt | 151 aa§ | 91 | |
| * , **HvPHP3 | 15857 | HPt (H-Q) | Pseudo-HPt | 127 aa | 45 | |
| Response Regulators | * , **HvRR1 | 11896 | REC | Type-A | 143 aa | 94 |
| HvRR2 | 11144 | REC | Type-A | 287 aa | 81 | |
| HvRR3 | 10973 | REC | Type-A | 173 aa§ | 75 | |
| * , **HvRR4 | c_601, c_1687 | REC | Type-B | 128 aa | 73 | |
| HvRR5 | 2421 | REC, MYB | Type-B | 684 aa§ | 84 | |
| * , **HvRR6 | 4929 | REC, MYB | Type-B | 562 aa | 41 | |
| * , **HvRR7 | 4245, 28937 | REC, MYB | Type-B | 602 aa | 41 | |
| * , **HvRR8 | c_1259 | REC, MYB | Type- B | 674 aa§ | 37 | |
| * , **HvRR9 | 14612 | REC, MYB | Type- B | 653 aa | 35 | |
| * , **HvRR10 | 4962, 35573, 17813 | REC, MYB | Type- B | 553 aa | 52 | |
| HvRR11 | c_1528, 3508 | REC, MYB | Type- B | 623 aa§ | 75 | |
| * , **HvRR12 | 44000 | REC | Type- B | 126 aa | 69 | |
| * , **HvRR13 | 13056 | REC, MYB | Type- B | 621 aa | 44 | |
| * , **HvRR14 | 3205 | REC, MYB | Type- B | 610 aa | 35 | |
| HvRR15 | c_473 | REC | Type- C | 134 aa§ | 56 | |
| HvRR16 | c_1495 | REC | Type- C | 134 aa§ | 58 | |
| * , **HvRR17 | 13700 | REC | Type- C | 92 aa | 63 | |
| * , **HvRR18 | 6171 | REC | Type- C | 133 aa§ | 53 | |
| **HvPRR1 | 29831, c_2383 c_1724 | REC (D-V) | Pseudo-RR | 182 aa | 42 | |
| **HvPRR2 | c_1185, 15192 | REC (D-A), MYB | Pseudo-RR | 347 aa | 42 | |
| HvPRR3 | 15567 | REC(D-E), CCT | Pseudo-RR | 759 aa§ | 69 | |
| HvPRR4 | 21515 | REC(D-E), CCT | Pseudo-RR | 604 aa§ | 66 | |
| HvPRR5 | 30930 | REC(D-E), CCT | Pseudo-RR | 522 aa§ | 76 |
Sequence information was complemented using public available EST databases and genomic sequences generated at the IPK Gatersleben. Prediction of coding sequences and protein sequences was done using FGENESH (http://linux1.softberry.com) and Augustus gene prediction (http://augustus.gobics.de) web-based interfaces.
noted domains are histidine kinase domain (HK), receiver domain (REC), GAF domain which is implicated in ethylene binding, CHASE domain for cytokinin binding, conserved histidine-containing phosphotransfer domain (HPt), Myb-like DNA binding domain (MYB), CCT motif found in clock proteins (CCT); brackets mark diverged domains and indicate changed amino acids,
not present in HarvEST 35,
not present in full-length cDNA collection of spring barley,
inferred amino acid sequences were compared with protein sequences computed in the Rice Genome Annotation project using the BlastP tool with the default settings,
full-length protein sequence.