Molecular Cloning and Sequence Analysis of the cDNAs Encoding Toxin-Like Peptides from the Venom Glands of Tarantula Grammostola rosea

Tarantula venom glands produce a large variety of bioactive peptides. Here we present the identification of venom components obtained by sequencing clones isolated from a cDNA library prepared from the venom glands of the Chilean common tarantula, Grammostola rosea. The cDNA sequences of about 1500 clones out of 4000 clones were analyzed after selection using several criteria. Forty-eight novel toxin-like peptides (GTx1 to GTx7, and GTx-TCTP and GTx-CRISP) were predicted from the nucleotide sequences. Among these peptides, twenty-four toxins are ICK motif peptides, eleven peptides are MIT1-like peptides, and seven are ESTX-like peptides. Peptides similar to JZTX-64, aptotoxin, CRISP, or TCTP are also obtained. GTx3 series possess a cysteine framework that is conserved among vertebrate MIT1, Bv8, prokineticins, and invertebrate astakines. GTx-CRISP is the first CRISP-like protein identified from the arthropod venom. Real-time PCR revealed that the transcripts for TCTP-like peptide are expressed in both the pereopodal muscle and the venom gland. Furthermore, a unique peptide GTx7-1, whose signal and prepro sequences are essentially identical to those of HaTx1, was obtained

鉄砲百合の球割に関する研究

1. In the northern climates of Japan, as in Hokkaido, the bulb production of Lilium longiflorum suffers from the following two defects, namely, reduction of size and production of so-called double nosed bulbs. To elucidate the condition of the formation of the double nosed bulbs, the various phases of the development of normal and diverse bulbs were studied from the morphological and physiological point of view, using two varieties, var. takesima and var. insulare as materials. 2. Anatomically, there appear generally two or three axils with equal chance for new bud initations, but usually only one develops, while the others remain flat. The accidental occurrance of double nosed bulbs is not a clonal character, but a physiological one caused by the development of an extra bud in the axil of the same or other scale leaf growing beside the first one, forming together the double nosed bulb afterwards. 3. The life history of the individual bud from the beginning to the end may be divided into the following six periods, namely, embryonic period, leaf forming period (scale leaf forming period and foliage leaf forming period), flower forming period (the initiation period and differentiation period of the flower organs), elongation period, flowering and fruiting period, and exfoliation period. 4. In Hokkaido the commencement of the embryonic period is recognized mostly in April when the mother bud attains about 2cm. in height, forming the primordium in the axil of the innermost scale leaf on the bulb, while in Saitama prefecture it occurs December to February. After the formation of foliage leaves (optimal temperature 24° to 30℃) in late summer in Hokkaido and in Saitama prefecture, the initiation of the embryonic flower bud (opt. temp. 18° to 23℃) occurs in October or November in Hokkaido (in Saitama, November). 5. The time of differentiation varies, however, according to the time of digging up and planting, though the slow elongation of the stem goes on invariably. This elongation of the stem with temperature optimum of 9° to 14℃ at the very beginning is retarded by the low temperature of winter in Hokkaido, while in Saitama it goes on incessantly. According to my observation, the inherent resting period of easter lily bulbs does not exist. 6. The relation between the periodic bulb development and the metabolic change of substances in bulbs was studied by chemical analyses, together with morphological observations simultaneously. The analyses were done on the five fractions, protein-N, soluble-N, reducing sugar, non-reducing sugar and starch, during the period from the beginning of April to mid October. 7. Generally speaking, the inner part of the bulb contains active nitrogen in great quantity, while the outer part of the bulb is rich in active sugar. As to each scale leaf, the active reserve substances, soluble nitrogen and reducing sugar are rich in its basal part. Total nitrogen content increases gradually from early spring to August, with a slight drop at the fruiting stage; then it increases again, until the final decline in October. At the time of rapid growth, from April to June, reducing sugar predominates exceedingly. Large amount of non-reducing sugar is recognized in summer and winter. Starch increases from spring onwards, but decreases after the early September. 8. If the reserve substences of young plant from seed and from bulblet are compared, the bulb of the former has more soluble nitrogen, protein nitrogen a little more reducing sugar than the latter, while the former has more non-reducing sugar than the latter. But these differences disappear in the progress of growth. 9. In comparing the reserve substances of normal and double nosed bulbs, the difference in these contents does not show any regular tendency. 10. Low temperature and severance of roots tend to induce the double nosed bulbs, which coincides nearly with that of the new bud formation. Other physical conditions, as mechanical pressure, light, humidity, hydrogen ion concentration etcetera, if acting singularly, are unable to induce the double nosed bulbs. 11. Most of double nosed bulbs in Hokkaido may be derived from the following two factors; (1) the low temperature of soil of 5 to 10cm. deep and (2) its rapid drop from late fall to early spring. 12. The degree and the duration of low temperature treatment are both responsible for the occurrence of double nosed bulbs, the 1° to 3℃ treatment being more effective than 5° to 7℃ treatment a greater drop being more effective than a less one. 13. Accordingly, shallow planting is liable to form a large number of unexpected double nosed bulbs. In the northern climates of Japan, it is therefore unavoidable to meet with the double nosed bulbs. 14. It seems reasonable, therefore, to plant bulbs in late August or early September in Hokkaido, though the condition is somewhat complicated. As for the desirable differentiation of root and bud, it is suitable to dig out the bulbs while the shoot is still green and plant the bulbs in the fields. When the formation of the foliage leaves in the bulb is manifested and the soil temperature tends to be 15° to 23℃, the bulbs should be planted quickly, different from the warmer regions, where no such treatment is needed. 15. To reduce the production of double nosed bulbs, the time of planting should be determined in accordance with the temperature and the phase of the development. The double nosed bulb is not so serious for forcing and bulb industry, when grown enough. There may be special use with them. It seems more recommendable to make efforts to produce substancial bulbs than to try to get out from the production of double nosed bulb