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Flower development plays vital role in horticultural plants. Post-transcriptional regulation via small RNAs is important for plant flower development. To uncover post-transcriptional regulatory networks during the flower development in Dimocarpus longan Lour. 'Shixia', an economically important fruit crop in subtropical regions, we collected and analyzed sRNA deep-sequencing datasets and degradome libraries Apart from identifying miRNAs and phased siRNA generating loci (PHAS loci), 120 hairpin loci, producing abundant sRNAs, were identified by in-house protocols. Our results suggested that 56 miRNA-target pairs, 22 21-nt-PHAS loci, and 111 hairpin loci are involved in posttranscriptional gene silencing during longan reproductive development. Lineage-specific or species-specific post-transcriptional regulatory modules have been unveiled, including miR482-PHAS and miRN15. miR482-PHAS might be involved in longan flower development beyond their conserved roles in plant defense, and miRN15 is a novel miRNA likely associated with a hairpin locus (HPL-056) to regulate strigolactone receptor gene DWARF14 (D14) and the biogenesis of phasiRNAs from D14. These small RNAs are enriched in flower buds, suggesting they are likely involved in post-transcriptional regulatory networks essential for longan flower development via the strigolactone signaling pathway. [ABSTRACT FROM AUTHOR]

Many real networks are embedded in space, and often the distribution of the link lengths r follows a power law, p(r) ~ r~s. Indications that such systems can be characterized by the concept of dimension were found recently. Here, we present further support for this claim, based on extensive numerical simulations of model networks with a narrow degree distribution, embedded in lattices of dimensions de = 1 and de -- 2. For networks with 8 < de,d is infinity, while for 8 > 2de, d has the value of the embedding dimension de. In the intermediate regime of interest de 8 < 2de, our numerical results suggest that d decreases continuously from d = oo to de, with d -- de oc (2 -- 8')/[8\8' -- 1)] and 8' = 8/de. We also analyze how the mass M and the Euclidean distance r increase with the topological distance Í (minimum number of links between two sites in the network). Our results suggest that in the intermediate regime de 8 < 2de, Mil) and r(l) increase with £ as a stretched exponential, M (I) ~ exp [Adti'(2-&')] and r(t) ~ exptA'0"8''], such that Mil) ~ r(l)d. For <5 < de, M increases exponentially with i (as known for 8 = 0), while r is constant and independent of i. For 8 Jä 2d,,, we find the expected power-law scaling, M{i) ~ idt and r(l) ~ t}!d™«, with dtdmm = d. In de = 1, we find the expected result, dt = dmi„ = 1, while in de = 2 we find surprisingly that although d = 2, dt >2 and dm¡„ < 1, in contrast to regular lattices. [ABSTRACT FROM AUTHOR]