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Incremental accretion of continental fragments from East Gondwana to Eurasia resulted in the growth of Asia and rise of the Tibetan Plateau, yet its detailed evolution remains uncertain. Argoland, a continental fragment that rifted from NW Australia during the Late Jurassic, played a key role in the initial opening of the Indian Ocean and the evolution of eastern Tethys. However, its present identity remains elusive, with East Java-West Sulawesi currently assumed to be the most likely option. To constrain the missing Argoland and its role in India-Asia convergence, we report new detrital zircon data from Sulawesi, Indonesia, and West Burma, Myanmar, and synthesize literature results from relevant regions in Southeast Asia, which (>15,000) reveal age profiles of West Sulawesi, the central Sulawesi metamorphic belt, and southeast Borneo comparable to that of Bird's Head, New Guinea, whereas age patterns of West Burma and East/West Java are similar to those of NW Australia. Notably, the most dominant age populations in NW Australia are rarely detected in Sulawesi and Borneo. These observations, combined with previous geological records and recent paleomagnetic data, suggest that West Burma is the mysterious Argoland, opposing the currently favored East Java-West Sulawesi model, with East Java and West Sulawesi probably having originated from NW Australia and Bird's Head, respectively. We estimate an average northward motion of ∼6–8 cm/yr for West Burma, which split from NW Australia to approach the equator during ca. 155–95 Ma, shedding new light on the reconstruction and breakup of northern East Gondwana, progressive building of Southeast Asia, and India-Asia convergence.

Before the India–Asia collision, Neotethyan subduction gave rise to an Andean-type convergent margin on the southern margin of Asia. To investigate the spatial and temporal distribution of the subduction-related magmatism, we undertook a combined determination of zircon U–Pb ages and Hf isotopes of Mesozoic to Paleogene intrusive and volcanic rocks from southern Tibet to Myanmar to characterize the two parallel magmatic belts that have previously been considered separately. One belt extends from the Gangdese Batholith in the Southern Lhasa sub-terrane to the Lohit Batholith, the Sodon Pluton and the Popa–Loimye Arc in the West Burma Block, and the other from the Central Lhasa Plutonic Belt to the Bomi–Chayu Batholith, the Dianxi Batholith and the Shan Scarps Batholith in central Myanmar. The Gangdese belt, as the main arc component, consists typically of I-type granitoids that contain magmatic zircons showing positive eHf(t) values. In contrast, the Central Lhasa Plutonic Belt belt is dominated by S-type granites in which most zircons show negative eHf(t) values suggesting the involvement of older continental crust in their petrogenesis. The distinct geochemical characteristics indicate not only distinct tectonic settings of their genesis but also the diverse nature of the crust forming the exotic continental ribbons amalgamated to Asia. Supplementary material: Details of sample locations and analytical results are available at: https://doi.org/10.6084/m9.figshare.c.4311485

To understand the geological control and tectonic forcing on the development of a major river system in SE Asia, new detrital zircon U-Pb and Hf isotopic data from the Salween drainage, Myanmar is reported. Three samples with a range of deposition ages corresponding to different tectonic periods of the Sibumasu Terrane reveal a dramatic change in the drainage system. Differing from the detrital compositions of modern sediments from the Salween river mouth, a Late Triassic sandstone sample shows zircon age distribution implying that the Salween drainage may have been connected at that time to the northeastern part of the Songpan-Ganzi Terrane and western part of the South China Block. U-Pb ages and ɛHf(T) isotopic data of detrital zircons from other major rivers in SE Asia, including the Yangtze, Red, and Mekong Rivers in the east and the Irrawaddy River and the Yalu-Tsangpo in the west are further synthesized. A marked discrepancy in zircons younger than Jurassic ages is identified. Similar to results from the Salween samples, these young zircons from the eastern rivers are overwhelmed by an old, recycled crustal component exhibiting negative ɛHf(T) values. In contrast, those from the western rivers are dominated by juvenile components that are characterized by high and positive ɛHf(T) values. The Salween drainage, therefore, lies in the frontier with its western outline broadly depicting the boundary between mature and juvenile crustal provinces in SE Asia.

Long non-coding RNAs (lncRNAs) are emerging as novel diagnostic markers of prostate cancer (PCa) and new determinants of castration-resistant PCa (CRPC), an aggressive and metastatic form of PCa. In addition to androgen receptor (AR) signaling, neuroendocrine differentiation (NED) is associated with CRPC. Recent reports demonstrate that the downregulation of repressor element-1 silencing transcription factor (REST) protein is a key step in NED of PCa cells. Here, we report HOTAIR as a novel REST-repressed lncRNA that is upregulated in NED PCa cells and in CRPC. HOTAIR overexpression is sufficient to induce, whereas knockdown of HOTAIR suppressed NED of PCa cells. Gene ontology (GO) analysis of differentially expressed genes under HOTAIR overexpression and in CRPC versus benign prostatic hyperplasia (BPH) suggests that HOTAIR may participate in PCa progression. Taken together, our results provide the first evidence of lncRNA HOTAIR as a driver for NED of PCa cells.

International audience; Deep tectonic processes are key integral components in the evolution of mountain belts, while observations of their temporal development are generally obscured by thermal resetting, retrograde alteration and structural overprinting. Here we recorded an integrated rock time-temperature history for the first time in the pro-wedge part of the active Taiwan arc-continent collision starting from sedimentation through cleavage-forming state to its final exhumation. The integrated thermal and age results from the Raman Spectroscopy of Carbonaceous Material (RSCM) method, zircon U-Pb laser ablation dating, and in-situ 40Ar/39Ar laser microprobe dating suggest that the basal accretion process was crucial to the development of the Taiwanese orogenic wedge. The basal accretion process commenced early in the mountain building history (∼6 Ma) and gradually migrated to greater depths, as constrained by persistent plate convergence and cleavage formation under nearly isothermal state at similar depths until ∼ 2.5 Ma recorded in the early-accreted units. Such development essentially contributed to mountain root growth by the increased depth of the wedge detachment and the downward wedge thickening during the incipient to full collision stages in the Taiwan mountain belt.

Fig. A.5. Plots of εNd (T) values vs. initial Sr isotope ratios for the samples from Myanmar. For comparison, the data of the Tengchong block from Liu et al. (2009), Monywa and Popa volcanos from Yang (2008), and the eastern Transhimalayan batholith, SE Tibet from Lin et al. (2012) are also shown.