Differential Expression of Rubisco in Sporophytes and Gametophytes of Some Marine Macroalgae

Rubisco (ribulose-1, 5-bisphosphate carboxylase/oxygenase), a key enzyme of photosynthetic CO2 fixation, is one of the most abundant proteins in both higher plants and algae. In this study, the differential expression of Rubisco in sporophytes and gametophytes of four seaweed species — Porphyra yezoensis, P. haitanensis, Bangia fuscopurpurea (Rhodophyte) and Laminaria japonica (Phaeophyceae) — was studied in terms of the levels of transcription, translation and enzyme activity. Results indicated that both the Rubisco content and the initial carboxylase activity were notably higher in algal gametophytes than in the sporophytes, which suggested that the Rubisco content and the initial carboxylase activity were related to the ploidy of the generations of the four algal species

Spatial Risk Assessment of the Effects of Obstacle Factors on Areas at High Risk of Geological Disasters in the Hengduan Mountains, China

The Hengduan Mountains in China are known for their complex geological environment, which leads to frequent geological disasters that pose significant threats to the safety and economic and social development of the local population. In this study, we developed develop a multi-dimensional evaluation index system from the aspects of economy, society, ecology, and infrastructure, and the resilience inference measurement (RIM) model was developed to assess resilience to regional disasters. The clustering evaluation of exposure, damage, and recovery variables in four states was conducted by way of K-means clustering. The results of K-means clustering are confirmed by discriminant analysis, and the disaster resilience index was empirically verified once. At the same time, the obstacle factor was further analyzed with the obstacle degree model. The results indicate that there are 8 susceptible areas, 23 recovering areas, 27 resistant areas, and 7 usurper areas. The classification accuracy of the model is 95.4%. The disaster resilience of high-risk areas was found to be low, with “extremely poor” differentiation, where the majority of the areas had low resilience and only a minority had high resilience. A “high in the southeast and low in the northwest” spatial distribution was observed. High-resilience areas were “dotted” and mainly concentrated in core areas with a high population density and strong economic activity, while low-resilience areas had a pattern of “edge extension” and were mainly distributed in the transition zone between the Qinghai–Tibet and Yunnan Plateaus. There were clear differences in the barriers of disaster resilience among the 65 counties (cities). The economic barrier degree was found to be the largest barrier to disaster resilience, followed by ecological, social, and infrastructure barrier degrees. The main factors affecting the distribution of disaster resilience in the high-risk areas were topographic relief, proportion of female population, cultivated land area, industrial structure, number of industrial enterprises above a designated size, and drainage pipeline density in the built-up area. Additionally, primary barrier factors classify the 65 counties (cities) into three types: economic constraint, natural environment constraint, and population structure constraint

Detection of hybridizing efficiency of the <i>rbcL</i> probe from <i>P. yezoensis</i>.

<p>The Dig High Prime DNA Labeling and Detection Starter Kit I (Roche) was used to detect the hybridizing efficiency of prepared RBCL probe. The probe was labeled with random primer. The control DNA (the first line) which was supplied by the kit was diluted as follows: 1, 1 ng/µL; 2, 10 pg/µL; 3, 3 pg/µL; 4, 1 pg/µL; 5, 0.3 pg/µL; 6, 0.1 pg/µL; 7, 0.03 pg/µL; 8, 0.01 pg/µL; 9, 0 pg/µL. Labeled probe (the second line) was diluted as follows: 1, 1×10⁻² dilution; 2, 1×10⁻⁴ dilution; 3, 3.3×10⁻⁴ dilution; 4, 1×10⁻⁵ dilution; 5, 3.3×10⁻⁵ dilution; 6, 1×10⁻⁶ dilution; 7, 3.3×10⁻⁶ dilution; 8, 1×10⁻⁷ dilution; 9, negative control (dd-water).</p

SDS-PAGE electrophoresis of the total soluble protein from gametophytes and sporophyte of <i>P. yezoensis</i>, <i>P. haitanensis</i>, <i>B. fusc-purpurea</i> and <i>L. japonica</i>.

<p>A, <i>P. yezoensis</i>. B, <i>P. haitanensis</i>. C, <i>B. fusc-purpurea</i>. D, <i>L. japonica</i>. (a), equal content of chlorophyll a per lane. (b), equal total soluble protein per lane. (c), equal fresh weight of material per lane. E, western blot of Rubisco of <i>P. yezoensis</i>. M, Maker. S, Sporophyte. G, Gametophyte. MG, Male gametophyte. FG, Female gametophyte.</p

Initial carboxylase activity of Rubisco from different generations of <i>P. yezoensis</i>, <i>P. haitanensis</i>, <i>L. japonica</i> and <i>B. fuscopurpurea</i>.

<p>Data are the mean value of three independent experiments (±SD).</p>S<p>: sporophyte;</p>G<p>: gametophyte;</p>M<p>: male gametophyte;</p>F<p>: female gametophyte.</p

Real-time PCR analysis for the absolute quantification (copy number, copies/µL) of rbcL gene in gametophyte and sporophyte of <i>P. yezoensis</i>, <i>P. haitanensis</i>, <i>B. fusc-purpurea</i> and <i>L. japonica</i>.

<p>Serial diluted cDNAs of each standard samples and unknown samples were amplified and detected by SYBR green and primers of rbcL gene. The quantity (copy number, copies/µL) of rbcL gene of each sample was calculated according to the corresponding standard curve, which was generated by plotting the Ct value against the logarithm of the quantities of the standard samples. A, <i>P. yezoensis</i>. B, <i>P. haitanensis</i>. C, <i>B. fuscopurpurea</i>. D, <i>L. japonica.</i> S, Sporophyte. G, Gametophyte. MG, Male gametophyte. FG, Female gametophyte. Data are the mean value of three independent experiments (±SD).</p

Real-time PCR analysis for the relative expression level (fold change) of rbcL gene in gametophyte and sporophyte of <i>P. yezoensis</i>, <i>P. haitanensis</i>, <i>B. fuscpurpurea</i> and <i>L. japonica</i>.

<p>The cDNA template was amplified and detected by SYBR green using primers of rbcL gene and two reference genes for each alga. A, <i>P. yezoensis</i>. B, <i>P. haitanensis</i>. C, <i>B. fuscopurpurea</i>. D, <i>L. japonica</i>. A-(a), B-(a), C-(a) and D-(a) are the results that use <i>18S</i> as the reference gene. A-(b) and B-(b) are the results that use <i>GAPDH</i> as the reference gene. C-(b) and D-(b) are the results that use <i>ACTIN</i> as the calibratorreference gene. S, Sporophyte. G, Gametophyte. MG, Male gametophyte. FG, Female gametophyte. Data are the mean value of three independent experiments (±SD).</p

Agarose gel electrophoresis of total RNA of gametophyte and sporophyte of <i>P. yezoensis</i>.

<p>A, result of native gel electrophoresis. B, result of formaldehyde-agarose gel electrophoresis. 1, Gametophyte. 2, Sporophyte.</p

Comparison of the effective PS II quantum yield (Y II) between gametophyte and sporophytes of <i>P. yezoensis</i>, <i>P. haitanensis</i>, <i>B. fuscopurpurea</i> and <i>L. japonica</i>.

<p>A, <i>P. yezoensis</i>. B, <i>P. haitanensis</i>. C, <i>B. fuscopurpurea</i>. D, <i>L. japonica</i>. S, Sporophyte. G, Gametophyte. MG, Male gametophyte. FG, Female gametophyte. Data are the mean value of three independent experiments (±SD).</p

Primers used in the qPCR assay.

<p><i>PY</i>: <i>P. Yezoensis</i>; <i>PH</i>: <i>P. Haitanensis</i>; <i>BF</i>: <i>B. Fuscopurpurea</i>; <i>LJ</i>: <i>L. Japonica</i>; F: Forward primer; R: Reverse primer; E_n, the primer's amplification efficiency.</p