Lauter F R, Marchfelder U, Russo V E, Yamashiro C T, Yatzkan E, Yarden O
BioInside GmbH, Teltow bei Berlin, Germany.
Fungal Genet Biol. 1998 Apr;23(3):300-10. doi: 10.1006/fgbi.1998.1038.
Blue light plays a key role as an environmental signal in the regulation of growth and development of fungi and plants. Here we demonstrate that in Neurospora crassa hyphae branch more frequently in cultures grown in light. Previous studies had identified cot-1 as a gene that controls apical hyphal cell elongation. In the cot-1 mutant, cessation of elongation is accompanied by hyperbranching. Here we demonstrate that the cot-1 gene encodes two transcript species of about 2100 nt (cot-1 (s)) and about 2400 nt (cot-1 (l)) in length and that the ratio of both transcript species abundance is photoregulated. The origin of the difference between cot-1 (l) and cot-1 (s) was localized to the 5' end of the cot-1 transcripts, suggesting that two COT1 isoforms with different activities may be formed. Both light effects, on branching and on cot-1 expression, were dependent on functional wc-1 and wc-2 gene products. In addition to light, L-sorbose comprises another environmental cue that controls hyphal branching in N. crassa. In the presence of L-sorbose, photoregulation of cot-1 was blocked, suggesting the involvement of alternative and potentially interdependent signaling pathways for the regulation of hyphal elongation/branching.
蓝光作为一种环境信号，在真菌和植物的生长发育调控中起着关键作用。在此我们证明，在光照条件下培养的粗糙脉孢菌菌丝中分支更为频繁。先前的研究已确定cot - 1是一个控制菌丝顶端细胞伸长的基因。在cot - 1突变体中，伸长的停止伴随着过度分支。在此我们证明，cot - 1基因编码两种长度约为2100 nt（cot - 1(s)）和约2400 nt（cot - 1(l)）的转录本，并且这两种转录本丰度的比例受到光调节。cot - 1(l)和cot - 1(s)之间差异的起源定位于cot - 1转录本的5'端，这表明可能形成两种具有不同活性的COT1异构体。光照对分支和cot - 1表达的影响均依赖于功能性的wc - 1和wc - 2基因产物。除了光照外，L - 山梨糖是另一种控制粗糙脉孢菌菌丝分支的环境信号。在L - 山梨糖存在的情况下，cot - 1的光调节被阻断，这表明可能存在替代的且潜在相互依赖的信号通路来调控菌丝伸长/分支。
