Vernalization promotes bolting in sugar beet by inhibiting the transcriptional repressors of BvGI.

Sugar beet (Beta vulgaris L.), a biennial sugar crop, contributes about 16% of the world's sugar production. The transition from vegetative growth, during which sugar accumulated in beet, to reproductive growth, during which sugar exhausted in beet, is determined by vernalization and photoperiod. GIGANTEA (GI) is a key photoperiodic flowering gene that is induced by vernalization in sugar beet. To identify the upstream regulatory factors of BvGI, candidate transcription factors (TF) that were co-expressed with BvGI and could bind to the BvGI promoter were screened based on weighted gene co-expression network analysis (WGCNA) and TF binding site prediction. Subsequently, their transcriptional regulatory role on the BvGI was validated through subcellular localization, dual-luciferase assays and yeast transformation tests. A total of 7,586 differentially expressed genes were identified after vernalization and divided into 18 co-expression modules by WGCNA, of which one (MEcyan) and two (MEdarkorange2 and MEmidnightblue) modules were positively and negatively correlated with the expression of BvGI, respectively. TF binding site predictions using PlantTFDB enabled the screening of BvLHY, BvTCP4 and BvCRF4 as candidate TFs that negatively regulated the expression of BvGI by affecting its transcription. Subcellular localization showed that BvLHY, BvTCP4 and BvCRF4 were localized to the nucleus. The results of dual-luciferase assays and yeast transformation tests showed that the relative luciferase activity and expression of HIS3 was reduced in the BvLHY, BvTCP4 and BvCRF4 transformants, which suggested that the three TFs inhibited the BvGI promoter. In addition, real-time quantitative reverse transcription PCR showed that BvLHY and BvTCP4 exhibited rhythmic expression characteristics similar to that of BvGI, while BvCRF4 did not. Our results revealed that vernalization crosstalked with the photoperiod pathway to initiate bolting in sugar beet by inhibiting the transcriptional repressors of BvGI.

Comparative proteomic analysis on chloroplast proteins provides new insights into the effects of low temperature in sugar beet.

BACKGROUND: Low temperature, which is one of the main environmental factors that limits geographical distribution and sucrose yield, is a common abiotic stress during the growth and development of sugar beet. As a regulatory hub of plant response to abiotic stress, activity in the chloroplasts is related to many molecular and physiological processes, particularly in response to low temperature stress. RESULTS: The contents of chlorophyll (Chl) and malondialdehyde (MDA), relative electrical conductivity (REL), and superoxide dismutase (SOD) activity were measured. The results showed that sugar beet could manage low temperature stress by regulating the levels of Chl, REL and MDA, and the activity of SOD. The physiological responses indicated that sugar beets respond positively to low temperature treatments and are not significantly damaged. Moreover, to determine the precise time to response low temperature in sugar beet, well-known abiotic stresses-responsive transcript factor family, namely DEHYDRATION RESPONSIVE ELEMENT BINDING PROTEIN (DREB), was selected as the marker gene. The results of phylogenetic analyses showed that BvDREBA1 and BvDREBA4 were in the same branch as the cold- and drought-responsive AtDREB gene. In addition, the expression of BvDREBs reached its maximum level at 24 h after low temperature by RNA-Seq and qRT-PCR analysis. Furthermore, the changes in chloroplast proteome after low temperature at 24 h were detected using a label-free technique. A total of 416 differentially expressed proteins were identified. GO enrichment analysis showed that 16 GO terms were significantly enriched, particularly chloroplast stroma, chloroplast envelope, and chloroplast thylakoid membrane. It is notable that the transport of photosynthetic proteins (BvLTD and BvTOC100), the formation of starch granules (BvPU1, BvISA3, and BvGWD3) and the scavenging of reactive oxygen species (BvCu/Zn-SOD, BvCAT, BvPrx, and BvTrx) were the pathways used by sugar beets to respond to low temperatures at an early stage. CONCLUSIONS: These results provide a preliminarily analysis of how chloroplasts of sugar beet respond to low temperature stress at the translational level and provide a theoretical basis for breeding low temperature resistant varieties of sugar beet.

Anatomical basis and design of the distally based lateral dorsal cutaneous neuro-lateral plantar venofasciocutaneous flap pedicled with the lateral plantar artery perforator of the fifth metatarsal bone: a cadaveric dissection.

BACKGROUND: Detailed investigation of the vasculature of the lateral aspect of the foot has rarely been presented. However, harvesting the flap in this area to cover defects of the foot and hand is highly important. Repair of soft-tissue defects at the forefoot remains a challenge in reconstructive surgery. This study explores the characteristics of the distal-based lateral dorsal cutaneous neuro-lateral plantar venofasciocutaneous flap pedicled with the lateral plantar artery perforator of the fifth metatarsal bone to establish a repair procedure for ulcers or defects in the forefoot region. METHODS: This study is divided into two parts: anatomical study and simulated operation. Thirty cadavers were utilized in the anatomical study after arterial injection. The tuberosity of the fifth metatarsal bone was used as the anatomical landmark. The lateral plantar artery perforator of the fifth metatarsal bone was identified through dissection. The perforators were dissected under a microscope. The details of the lateral plantar artery perforators, the distribution of the lateral dorsal cutaneous nerve and lateral plantar vein, the anastomosis in the lateral plantar artery perforator of the fifth metatarsal bone, the nutrient vessels of the lateral dorsal cutaneous nerve and lateral plantar vein, and other arteries of the lateral foot were recorded. The flap-raising procedure was performed on three fresh cadavers. RESULTS: The lateral dorsal cutaneous nerve originated from sural nerve, traveled obliquely downward along the anterior lateral margin of the foot, and accompanied by the lateral plantar vein after bifurcation, and was eventually distributed on the lateral aspect of the foot. The nutrifying arteries to the lateral dorsal cutaneous nerve and lateral plantar vein were present segmentally and mainly originated from the lateral plantar artery perforator of the fifth metatarsal bone. These nitrifying arteries constantly originated from the lateral plantar artery in the area of tuberosity of the fifth metatarsal, ran along the medial side of the fifth metatarsal, traveled between the fifth metatarsal bone and the lateral muscle group (the flexor digitorum brevis and the abductor digiti minimi muscles), pierced the aponeurosis, vascularized the skin of the anterior lateral plantar region, and resulted in many minute branches, which anastomosed with the lateral tarsal artery and fourth dorsal metatarsal artery. The anatomical study showed that (1) the vasculature pattern can roughly be classified into three types and (2) constant anastomoses occurred between the above-mentioned arteries in the lateral-dorsum region of the foot. CONCLUSION: A reliable large- or medium-sized neuro-venocutaneous flap with lateral dorsal cutaneous nerve, lateral plantar vein, and nutrient vessels can be raised using only the perforator of the lateral plantar artery of the fifth metatarsal bone, which is thin, is in the immediate vicinity of the forefoot, and has a reliable retrograde blood supply. This flap can be considered an alternative means to reconstruct soft-tissue defects of the forefoot.

Anatomic basis and clinical application of the distally based medialis pedis flaps.

BACKGROUND: Soft-tissue defects of the forefoot are difficult to cover adequately, particularly, although multiple options for reconstruction are available. This study especially focused on the vascularization of the medial side of the foot and the determination of the contribution of the nutrient vessels to medialis pedis flap viability. METHODS: Thirty cadavers were available for this anatomical study. Microdissection was conducted under a microscope, and details of the course and distribution and the communication of the first plantar metatarsal artery with the fascial vascular network of the medial side of the foot were recorded. Clinically, six cases of soft-tissue defects at the forefoot region were reconstructed with distally based medialis pedis flap. RESULTS: The perforator of the first plantar metatarsal artery pierces in the superficial fascia of the medial aspect of the foot 2.2 ± 0.7 cm proximal to the first metatarsophalangeal joint, vascularize the skin of the medial plantar region. The anatomical study showed that the vasculature pattern could roughly be classified into two types. In terms of clinical application, all flaps completely survived, and one patient had partial loss of skin graft. CONCLUSION: The perforators of the medialis pedis flap are presented constant. The forefoot region can be repaired by the distally based medialis pedis flap on the perforator of the medial plantar artery of the hallux or the first plantar metatarsal artery perforator with medial plantar vein, medial plantar cutaneous nerve and nutrient vessels.

Anatomic basis of the distally based venocutaneous flap on the medial plantar artery of the hallux with medial plantar vein and nutrient vessels: a cadaveric dissection.

PURPOSE: This study aims to identify a repair procedure for ulcers or defect of the forefoot region. The general distribution and variation of the vascular anatomy of the distally based venocutaneous flap on the medial plantar artery of the hallux with medial plantar vein and nutrient vessels were investigated. This study especially focused on the vascularization of the medial side of the foot and the determination of the contribution of the nutrient vessels of medial plantar vein and medial dorsal cutaneous nerve to flap viability. Experiments were conducted to obtain information for operating procedures and to understand the vascular reliability of the flap. METHODS: Thirty cadavers were available for this anatomical study after arterial injection. The tuberosity of the fifth metatarsal bone was adopted as the anatomical landmark. Microdissection was conducted under a microscope, and details of the course and distribution of the medial plantar vein and the communication of the medial plantar artery of the hallux with the fascial vascular network surrounding the medial plantar vein were recorded. The flap-raising procedure was performed in a fresh cadaver specimen. RESULTS: The medial plantar vein was incorporated by the medial end of the dorsal pedal vein arch and medial dorsal vein of the hallux around the first metatarsal-medial cuneiform joint. It traveled along the medial margin of the foot and drained into the great saphenous vein at the level of the medial malleolar. The outer diameter of the nerve at the intermalleolar line was 3.2 ± 0.5 mm. These nutrifying arteries to the medial plantar vein were present segmentally and mainly came from the medial plantar artery of the hallux, which traveled forward in the fascia between the abductor hallucis tendon and the first metatarsal bone, emerged into the superficial layer 2.2 ± 0.7 cm proximal to the first metatarsophalangeal joint, and gave off many minute branches. These branches communicated with the fascial vascular network surrounding the medial plantar vein, supplying the fascia and integument of the medial foot. CONCLUSION: Reliable venocutaneous flap with medial plantar vein and nutrient vessel flaps can be raised based solely on the perforator of the medial plantar artery of the hallux. This flap should be considered as a preferential way to reconstruct soft-tissue defects of the forefoot.