HD-Zip proteins modify floral structures for self-pollination in tomato.

Cleistogamy is a type of self-pollination that relies on the formation of a stigma-enclosing floral structure. We identify three homeodomain-leucine zipper IV (HD-Zip IV) genes that coordinately promote the formation of interlocking trichomes at the anther margin to unite neighboring anthers, generating a closed anther cone and cleistogamy (flower morphology necessitating strict self-pollination). These HD-Zip IV genes also control style length by regulating the transition from cell division to endoreduplication. The expression of these HD-Zip IV genes and their downstream gene, Style 2.1, was sequentially modified to shape the cleistogamy morphology during tomato evolution and domestication. Our results provide insights into the molecular basis of cleistogamy in modern tomato and suggest targets for improving fruit set and preventing pollen contamination in genetically modified crops.

A gradient of the HD-Zip regulator Woolly regulates multicellular trichome morphogenesis in tomato.

Homeodomain (HD) proteins regulate embryogenesis in animals such as the fruit fly (Drosophila melanogaster), often in a concentration-dependent manner. HD-leucine zipper (Zip) IV family genes are unique to plants and often function in the L1 epidermal cell layer. However, our understanding of the roles of HD-Zip IV family genes in plant morphogenesis is limited. In this study, we investigated the morphogenesis of tomato (Solanum lycopersicum) multicellular trichomes, a type of micro-organ in plants. We found that a gradient of the HD-Zip IV regulator Woolly (Wo) coordinates spatially polarized cell division and cell expansion in multicellular trichomes. Moreover, we identified a TEOSINTE BRANCHED1, CYCLOIDEA, and PROLIFERATING CELL NUCLEAR ANTIGEN BINDING FACTOR (TCP) transcription factor-encoding gene, SlBRANCHED2a (SlBRC2a), as a key downstream target of Wo that regulates the transition from cell division to cell expansion. High levels of Wo promote cell division in apical trichome cells, whereas in basal trichome cells, Wo mediates a negative feedback loop with SlBRC2a that forces basal cells to enter endoreduplication. The restricted high and low activities of Wo pattern the morphogenesis of tomato multicellular trichomes. These findings provide insights into the functions of HD-Zip IV genes during plant morphogenesis.

A HD-ZIP transcription factor specifies fates of multicellular trichomes via dosage-dependent mechanisms in tomato.

Hair-like structures are shared by most living organisms. The hairs on plant surfaces, commonly referred to as trichomes, form diverse types to sense and protect against various stresses. However, it is unclear how trichomes differentiate into highly variable forms. Here, we show that a homeodomain leucine zipper (HD-ZIP) transcription factor named Woolly controls the fates of distinct trichomes in tomato via a dosage-dependent mechanism. The autocatalytic reinforcement of Woolly is counteracted by an autoregulatory negative feedback loop, creating a circuit with a high or low Woolly level. This biases the transcriptional activation of separate antagonistic cascades that lead to different trichome types. Our results identify the developmental switch of trichome formation and provide mechanistic insights into the progressive fate specification in plants, as well as a path to enhancing plant stress resistance and the production of beneficial chemicals.

H and HL synergistically regulate jasmonate-triggered trichome formation in tomato.

The development of trichomes, which protect plants against herbivores, is affected by various stresses. In tomato, previous studies showed that stress triggered JA signaling influences trichome formation, but the underlying mechanism is not fully resolved. Here, we found two C2H2 zinc finger proteins synergistically regulate JA-induced trichome formation in tomato. The naturally occurring mutations in H and its close homolog H-like gene in a spontaneous mutant, LA3172 cause severely affected trcihome development. Compared with respective single mutant, h/hl double mutant displayed more severe trichome defects in all tissues. Despite the partially redundant function, H and HL genes regulate the trichome formation in the spatially distinct manner, with HL more involved in hypocotyls and leaves, while H more involved in stems and sepals. Furthermore，the activity of H/HL is essential for JA-triggered trichome formation. JA signaling inhibitor SlJAZ2 represses the activity of H and HL via physical interaction, resulting in the activation of THM1, a negative regulator of trichome formation. Our results provide novel insight into the mechanism of the trichome formation in response to stress induced JA signaling in tomato.

Multimodal ultrasound imaging of persistent urogenital sinus with uterus didelphys and double vagina malformation: A case report.

RATIONALE: Persistent urogenital sinus (PUG) with uterus didelphys and double vagina is a rare urogenital anomaly. The diagnosis is based on magnetic resonance examination and cystoscopy. To the best of our knowledge, there is no literature report of PUG diagnosed by ultrasound alone. PATIENT CONCERN: A 23-year-old woman presented with atypical menstruation and recurrent hematuria for 13 years and recurrent lower abdominal pain for 12 years. DIAGNOSIS: PUG was diagnosed through multiple ultrasound modalities, including transabdominal 2-dimensional ultrasound, transrectal bi-plane high-frequency ultrasound, and contrast-enhanced ultrasound. We diagnosed this malformation preoperatively by accurately measuring the length of urethra and common channel through multimodal ultrasound imaging. INTERVENTIONS: Urethra separation and reconstruction, vaginal pull-through and artificial vaginoplasty, and bilateral hysterosalpingectomy were performed. OUTCOMES: The postoperative course was uneventful. She was urinating normally after half a year and used continuous vaginal dilatation to avoid stenosis. LESSONS: PUG associated with uterus didelphys and double vagina is an extremely rare malformation of the reproductive system. Multimodal ultrasound imaging can be used to diagnose this malformation preoperatively clearly and to accurately measure the length of urethra and common channel, providing an imaging basis for preparing an operative plan.

[Chemical Constituents from Callicarpa nudiflora].

OBJECTIVE: To study the chemical constituents of Callicarpa nudiflora. METHODS: The chemical constituents were isolated and purified by column chromatography on silica gel, ODS, Sephadex LH-20 and MPLC. Their structures were elucidated on the basis of physicochemical properties and special analysis. RESULTS: Eleven compounds were isolated from the leaves of Callicarpa nudiflora, whose structures were elucidated as 2α,3α-dihydroxyurs-12-en-28-oic acid (1), isorhamnetin (2), 2α,3ß,19α-trihydroxyurs-12-en-28-oic acid(3), 2α,3α,19α,23-tetrahydroxyurs-12-en-28-oic acid(4), 2α,3α,19α-trihyhydroxy-olean-12-en-28-O-α-D-glucopyranoside (5), benzyl-4'-hydroxy-benzoyl-3'-O-ß-D-glucopyranoside(6) (3S,5R,6R,7E,9S)-megastigman-7-ene-3,5,6,9-tetrol(7), philonotisflavone(8), 1, 6-di-O-caffeoyl-ß-D-glucopyranoside (9), luteolin-4'-O-(6"-E-caffeoyl)-ß-D-glucopyranoside (10), and (6S, 9R)-roseoside(11). CONCLUSION: All compounds are isolated from this plant for the first time.